Mughal Forts on Fluvial Terrains in Dhaka

Description

The property Mughal Forts in Fluvial Terrains in Dhaka consists of four sites associated with the Mughal military and administrative establishment in Bengal. The sites include three naval forts in the outskirts of Dhaka City: Hajiganj Fort, Sonakanda Fort and Idrakpur Fort, and one palace fort Lalbagh Fort in Dhaka City. The forts were established by the Mughal Subahdars (Viceroys) appointed to govern Subah-e-Bangla (the Bengal Province), with Dhaka being the capital between 1610 and 1717 CE. The forts’ designs adapted to the deltaic landform of Bengal as contrasted with the mainstream Mughal architecture elsewhere in the Indian Subcontinent.

The Hajiganj Fort was built around 1610 CE. According to Bahrishtan-i-Ghaybi, a 17^th-century chronicle on the history of Bengal, Cooch Behar, Assam and Bihar by Mirza Nathan, a Mughal general in Bengal, the fort was extensively used by Mughal subahdar Islam Khan as a military base for operations against the Bara Bhuiyans (an alliance of local landlords).

Mughal Subahdar Mir Jumla is popularly credited for establishing the Sonakanda Fort and Idrakpur Fort between 1660 and 1663 CE. Together with the Hajiganj Fort, these two forts formed a strategic defence mechanism for protection from the Magh/Arakanese, Portuguese and Dutch pirates coming from the Bay of Bengal via river routes and to suppress local landlords. Although the Mughals military forces predominantly included cavalry, infantry, and artillery divisions, they had to develop a navy to conquer and control the riverine delta of Bengal and to defend the capital where these forts acted as the base for military operations.

The Lalbagh Fort, originally called ‘Qila Aurangabad’, is in the capital Dhaka. The fort construction was initiated by Mughal Subahdar Mohammad Azam Shah, the third son of Emperor Aurangzeb, in 1678 CE. This ambitious attempt was undertaken when Dhaka became relatively secured from the previous threats of rebellious landlords and pirates, for which the naval forts played a crucial role. After 15 months of his appointment, the emperor called upon him to suppress the Maratha rebellion. Subahdar Shaista Khan continued the construction but left it incomplete after the death of his daughter Iran Dukht (Pari Bibi) in 1684 CE, who was also the fiancé to Prince Azam. In 1844, an autonomous institution named ‘Dhaka Committee’ started preserving the fort, and since then, it is known as the ‘Lalbagh Fort’. The fort came under the jurisdiction of the Department of Archaeology in 1910 CE.

Table 1: Names and locations of the property components

Bengal is located on the enormous delta of the Ganges-Brahmaputra Rivers, and the geography was quite unknown to the Mughals. The imperial armies were also challenged by the annual rain and the abundance of rivers and canals. The landscape dominated by various shapes and water bodies converts into a continuous water plane during the monsoon. The Mughals struggled and had to adapt themselves to cope up with such conditions. Due to the rivers, rains and flood of this deltaic terrain, the wars became amphibious. During the first two decades of their expedition in Bengal, the Mughals naval warfare technique was inefficient, and their opponents, the local chieftains, had large supplies of war-boats. Although Tanda and Rajmahal in the western Bengal were conquered, the Mughals could not enter the river-infested eastern delta until the appointment of Raja Man Singh as the Mughal Subahdar of Bengal in 1594. Under his supervision, the Mughals started to deploy an increasing number of war-boats. By the time Islam Khan Chisti assumed the leadership of the Mughal expedition in 1607 CE, the Mughals were using hundreds of boats for battle. Islam Khan was further challenged by the Arakan state of coastal Burma and the Portuguese pirates who settled in the coastal area of South-eastern Bengal. The Arakanese rulers considered the advent of the Mughals as a threat and, in response, operated naval expeditions to secure their territory, especially after 1614 CE. By 1620 CE, these attacks were further supplemented by the naval raids by the Portuguese and few Dutch Pirates who came in search of slaves, food-grain, and booty. Several attempts of the Mughals to conquer the Arakan state failed as the opponents were very proficient in naval warfare.

Dhaka, being in the centre of eastern Bengal, was able to command all the big river routes. Situated on higher ground in a low-lying region, Dhaka stands on the northern bank of the River Buriganga. This river, about 26 miles in length, takes off from the River Dhaleswari, a little below Savar, and flows down to the north of Narayanganj; and through these two rivers, Dhaka is connected by water with great rivers, namely Ganges (Padma), the Meghna and Brahmaputra. In addition, the network of the river system of Bengal is so extended that through this network the remote parts of the land are accessible. Islam Khan decided to use this advantage to intensify the campaign against the rebellious and independent Bara–Bhuiyans (Zamindars), Afghan kingdoms, and to establish Mughal hegemony in Bengal with Dhaka as the capital. Therefore, he shifted the capital from Rajmahal to Dhaka and Dhaka was renamed as Jahangirnagar after the emperor. Mughals were attracted by the wealth of Bengal, and the shift of capital from Rajmahal to Dhaka was also necessary to secure revenue and operate trade from Bengal.

Bengal Subah became the wealthiest province of the Mughal empire. Bengal generated significant percent of the empire’s GDP. It gained global leadership in industries such as textile manufacturing and shipbuilding Dhaka eventually became the empire’s financial capital, with a population exceeding one million. Silk and cotton textiles, steel, saltpetre, and agricultural and industrial products were exported from Dhaka.

Previously, Sonargaon, the capital of the Bara-Bhuiyans maintained the dominant position in Bengal in terms of economic prosperity for about two hundred years throughout the independent Sultanate of Bengal (1338-1538 CE). Sonargaon’s position on the Meghna bank gave it the first importance as an inland port town in the medieval history of Bengal. Sonargaon’s economic importance was destroyed through the defeat of Isa Khan’s son Musa khan by the force of the Mughal Subahdar Islam Khan (1608-1613 CE) in (1611 CE). Sonargaon lost its importance because of the shifting of the course of the river Meghna, although as a place of cotton fabrics production, it managed to retain its own position till the foreign competition ruined its trade.

Several items like jute, unrefined sugar, mustard seed, oil, honey, wax, ivory, shell lack, ghee, betel nut, cloths, linseed, cheese, turmeric, mats etc. were imported from different places of Eastern Bengal such as Chandpur, Sylhet, Manikganj, Narayanganj, Bhawal, Kishoreganj, Barisal, Cumilla, Habiganj, Nayarhat, Mymenshing, and Mirzapur. They were mostly exported to Patna, Calcutta, and Murshidabad. A certain amount of the commodities was used for the consumption of the city dwellers, and the remaining amount distributed to other places through the inland markets.

All the manufacturers of fine cotton fabrics, particularly ‘muslins’, were positioned within the area Dhaka district, namely at ‘Dhaka city, Sonargaon, Dhamrai, Teetabari (on the left bank of the Shitalakhya river), Jangalbari (left bank of the Brahmaputra), Bajitpur (about 18 miles from Jangalbari) and Bikrampur. Bengal’s production of fine cotton included muslins, rugs, veils of various colour, gauzes (a thin translucent fabric of silk, linen, or cotton), and material of turbans, embroidered silk, and brocaded taffetas.

Dhaka also had a mint (Takshal) which produced money (coins) from the Mughal period to even first few years of company years (British East India Company). The earliest Dhaka-produced coin found is from 1617 CE. Dhaka gradually achieved great commercial importance and became the most reputed trading centre during this period. As mentioned by A. H. Dani, from an almost insignificant position (a military outpost of the Mughals and the headquarters of their Thanadar) Dhaka, due to its strategic location and the capacity to monopolize the trade and commerce, became the queen of the cities of Eastern India.

The Mughals set up their first military force in Dhaka during the reign of Emperor Akbar, but the importance of the area in terms of the naval strategy was only felt during Subahdar Islam Khan’s ‘Bhati Campaign’ against Musa Khan in 1608 CE. The previous capital Rajmahal was abandoned as the change of the course of Ganges made the city inaccessible to war-boats and unsuitable to naval defence.

The location of Dhaka was suitable as a base of operation against the Bara-Bhuiyans and also as a convenient base from which a close watch on the usual routes followed by the pirates could be maintained.

Various kinds of projectile weapons had been used in amphibious warfare. Apart from archers and matchlock men, a great deal of artillery was deployed by the Mughals; in contrast to the warfare techniques of north India, the river and the canals aided to allow the imperial armies to move around heavy artilleries easily. They also learnt the technique of mounting cannons on big boats such as ghurabs from their local adversaries, boatmen and Portuguese mercenaries. The artillery carrying war-boats were also used for besieging fortified positions on land. In general, matchlock men were predominantly used by the Mughals in the riverine terrain of Bengal rather than the horsemen as projectile weapons deemed useful in this particular geographic condition. The water bodies lowered the possibility of close combat and engaged each other from a distance.

By the end of the 16th century, the Portuguese mercenaries and renegades fled from Goa towards the coastal areas of Bengal and took employment in the armies of local and Afghan chieftains and later in the Mughal Navy.

The availability of riverine silt and mud drove the Mughal armies to develop a new type of fortress warfare in this region. They observed that the local Afghan and Bengali adversaries used to construct improvised mud fortifications for defence. This phenomenon was quite different from the stone forts that the Mughals used to encounter in North India. These mud forts were very rapidly built by the cheap labour of local boatmen and were placed in strategic locations to command riverine communication in terms of defence. Despite being inexpensive, these forts were remarkably resilient in terms of their purpose. The mud walls used to absorb the force of cannons shells and did not break as opposed to the stone walls of north Indian forts. Even a small mud garrison could perform very well to defend and took a lot of efforts to besiege. The Mughals had to spend a significant amount of resources to subdue the local mud forts in their early campaign during 1608-1612 CE.

The naval forts of the Bhuiyans were strongly built and raised at a few kilometres off from the mouth of the confluence of important river routes while maintaining internal links through canals. As soon as the news of the enemy’s arrival reached, the war-boats were pushed down to the main confluence in series through the canals. The Bhuyians also possessed harbours close to their respective capitals for building and repairing boats and impart naval training to the soldiers. Harbours of Dhumghar (of Raja Pratapadiya), Sripur (of Raja Kedar Rai), Sonargaon (of Musa Khan) are noteworthy.

Realizing the efficiency and military value of these mud forts considering the geographic features, the Mughal themselves started constructing mud forts for defence and later strengthening the important forts with brick masonry and lime mortar and installing heavy artillery inside them.

Among the naval forts, the Hajiganj fort was frequently used by Islam Khan to command military operations against the Bhuyians. The Sonakanda and Idrakpur forts were built after the Hajiganj fort. These forts, together with several outposts, performed as a defence centre to protect Dhaka from external enemies. Subahdar Mir Jumla extensively used these forts and conducted military expeditions. There were several other smaller forts, establishments or outposts which supplemented these three forts such as the Afghan fort of Beg Murad, Jinjira fort, Dhapa fort, Katrabhu fort, Old fort at Fatullah, Pagla Bridge and Octagonal structure at Mughlai Char. Most of these establishments have been lost over time and some are in very dilapidated condition.

As the Bhuiyans and the pirates possessed strong naval forces and war-boats, the Mughals felt the necessity of navy and naval strategy. Hence, the Mughals had to undertake the task of organizing a naval department (titled Nawara), constructing war-boats, raising naval forces and docks and planning naval expeditions in addition to their well-established infantry and cavalry divisions. The naval strategy in Bengal was developed on the mobility of their war-boats, naval guardhouses at strategic places, the process of sounding the depth of the rivers, the Nawara grants in the coastal region and defensive measures. Amla-e-Nawara was the Mughal naval fleet which had 768 vessels with its headquarter in Dhaka. It had a large army, including 933 Portuguese men. Amla-e-Assam was an army of 8,112 men with artillery to Eastern Frontier Provinces stationed at Dhaka.

The flotilla of war-boats rather than cavalry was more effective in the warfare in eastern Bengal. Being aware of this, the Mughals increased their collection of war-boats and also significantly increased their skill in military use of boats. From the narrative of the ‘Review of boats at Shahzadapur’ in Baharistan, it becomes apparent that the fleet of Mughal war-boats comprised various types of boats, such as Katari, Maniki, Bathila, Kusa, Khelna, and Gondola. Large cannons and Zabarzangs (field pieces) were mounted on Katari, Manaki, and Bathila. These boats were quite big, and on the gangway of each boat (a line of), wagons (one kind of trading cargo which was called thattari and which was used as a barrier against enemy attack) were displayed.

Furthermore, constructing a temporary bridge via using boats to cross over rivers was a significant move displayed by the Mughals. As narrated in Baharistan, to cross the river Ichamati, Admiral Ihtimum Khan and his son Mirza Nathan constructed a bridge with the boats of the traders. It also suggests that during the raid of the Magh king, two thousand horsemen and four thousand expert men with matchlock were transferred over such a bridge. Boats were also used as the personal transport of the statesmen of Bengal as well as of admiral and other important naval officers. The name of Islam Khan’s boat was ‘Chandni’, which was also called ‘Fath-iDariya’ (Triumph of the sea). The names of the personal boats of Ihtimam Khan and Mirza Nathan were ‘Jal- Tarang’ and ‘Qutb-Asan’ (a kutal suwari kusa), respectively.

The Mughals also included war elephants in their campaign to directly assault the mud-forts since artillery fire in general proved to be inefficient against them. The elephants were also used for carrying troops and resources across the rivers. Campaigns against Arakan, Tripura, Bokainagar and Kamrup involved the inclusion of a large number of elephants. The prominence of war elephants in terms of number and tactical importance was greater than most other parts of North India.

The Mughal armies enabled them to establish themselves as a dominant power of the Bengal delta by showing remarkable geographical and military adaptability over a period of around 100 years.

During its tenure as a provincial capital, Prince Shah Suja, the subahdar, temporarily shifted the capital to Rajmahal in 1639 CE, virtually forfeiting the control over a large portion of southeastern Bengal. Shaista Khan eventually managed to stall the raids from the Portuguese pirates and threatened them into an alliance with the empire and conquered Chatgaon (now Chottogram) with a reorganized war-fleet in 1666 CE.

After conquering Chatgaon and bringing the Portuguese as well as several other European traders on board in terms of trade and commerce, Dhaka became the financial capital of the Mughal Empire. The phenomenon can be reflected in the appointment of Prince Azam as the subahdar of Bengal and eventually the initiation of Qila Aurangabad/ Lalbagh Fort as his residence, administrative centre, and fortified defence. The fort’s location by the river Buriganga further reinforced the previous mechanism of naval defence of the city. The spatially elaborate organization of various functions was an ambitious attempt by the Mughals in Dhaka. Although this fort was not completed, it remains as the largest and enthusiastic venture taken up by the Mughals in the Bengal and can be associated as an iconic landmark of Dhaka.

Location
Located in Narayanganj Sadar Upazilla, Narayanganj District, Dhaka Division. The fort is situated on the western bank of the river Shitalakhya. The location was a previous discharge point of river Buriganga. The area, as well as the fort, was formerly known as Khizirpur. The fort is about 15 kilometres from Dhaka city.

Description
The fort was originally built on a riverbank; however, the channel shifted its course towards the east over time.

The fort has a non-symmetric hexagonal plan. The platform of the entire fort is elevated approximately 1.5m from the ground level. The fort covers an area of almost 250m x 250m and is elongated in the east-west direction. The surrounding walls are about 0.91m thick and almost 1.83m high. There is a 1.22m high and 0.61m wide rampart walkway on the inner side of the fortified wall for operating muskets against the enemy. There are six circular bastions at each corner, among which the three located on the southern and eastern side measures 9.04m in diameter and the three located on the northern and western side measures 3.95m in diameter. The southern bastion’s seven-step pyramidal artillery platform suggests that the gun platforms at Hajiganj fort aimed south (presumably over the river’s former course) cut across from the Sitalakhya to the Buriganga).

The north wall possesses the only gateway, which is a four-centred archway placed within a rectangular frame. There are several plastered panels on both sides of the gateway. The top of the gateway is decorated with merlons. The gateway comprises an inner and an outer staircase. The outer staircase has a flight of eighteen steps, measuring 5.07m wide (provided with two wide sidewalls), while the inner staircase has a flight of eight steps, measuring 3.4m wide, and the interior archway is 19.16m high and 15.92m wide. The arched gateway is embellished with rectangular niches.

There is a barren, locus standi and grandiloquent tower with spiral stairs of brickwork in the eastern corner of the fort ground. This is the only internal structure within the fort area. Construction of a large plinth with three pillars and a staircase has been found alongside the north and northeast side of the fort.

The entire fortification wall and bastions are crowned by numerous big merlons perforated with varying loopholes for muskets. The loopholes are not uniform in size or number. Both the merlons and loopholes were used for operational purpose rather than decorative reason.

The Hajiganj fort is entirely constructed with brick and covered with plaster.

Location
The Sonakanda Fort is located in the Enayetnagar village of Kolagachchia union under Narayanganj Bandar Upazila in Narayanganj district. The fort stands on the eastern bank of the river Shitalakhya just at the point where formerly it met the river Brahmaputra. It has been placed to the south of the point where the Triveni Khal (Canal) takes off from the Sitalakhya, which flows along the fort’s western side. It is almost 17km away from the capital, Dhaka.

Description
The fort has a quadrangular rampart wall with a central courtyard in the east and a raised artillery platform on the west overlooking the river shaped like a round drum with a considerably large diameter. Large cannons were mounted in this strategic position.

The quadrangular portion covers an area of 86.56m x 57.0m, and the only entrance is located to the north. The fort is built with brick and covered with plaster. The brick size is 19.05 x 9.89 x 3.81cm.

The entrance gateway is placed within a rectangular frame with rosette engraved spandrel and several plastered panels in its inner and outer walls. The façade of the gateway is projected within a semi-octagonal shape. The gateway is topped by merlons. The surrounding wall is 3.39m high and 1.06m thick. The merlons have loopholes placed 0.91m from the top, 1m high on an average, and the bottom is built solid, and those are envisaged to have been used to put guns aiming at the enemies through their loopholes.

The rectangular portion of the Sonakanda fort has four octagonal corner bastions crowned with merlons containing loopholes. The northwest and south-west bastions facing the river have a diameter of 6.85m and are 3.39m high, including the crenulation. The northeast and southeast bastions have a diameter of 4.26m and are 3.39m high. All the circular bastions are linked by a 2.5-meter narrow walkway from inside. The bastions are capped with loopholes and several open and closed arches, but the arrangement and number of loopholes are not similar.

A staircase on the west side leads up to the circular raised platform entered by a cinquefoil archway with a flight of 25 steps up from the courtyard. The three-stage staircase is 16.15m long in plan. The artillery platform is 6.09m high from the ground level. It comprises two circles: the inner circle is 15.24m in diameter, and the outer circle is 21.75m in diameter. The thickness of the surrounding wall of the platform is 0.91m. The platform is surmounted by 32 merlons (five cusped) with loopholes that are 0.97m thick and 1.91m high.

Location
The Idrakpur fort was positioned on the north bank of the river Ichamati in the Idrakpur region of Munshiganj district, about 24 km from Dhaka. The river has shifted its course over the years and is currently flowing about 1.6 km away from the fort.

Description
The fort has two parts separated by a screen wall. The western part covers an open area measuring 97m x 51.80m internally and surrounded by a wall with four similar corner bastions with 6.09m diameter and 4.6m height. The bastions have loopholes. The eastern part measures 77m x 44m and includes a solid circular platform in the middle and a small bastion at its north-eastern corner. The circular platform is 32.9m in diameter and is placed at 24m above the ground level. The platform is accessed through a 1.9m wide flight of steps across the eastern side of the defence wall, which is 18.26m long in plan. Another 9-step staircase leads down into the basement chamber at the foot of the staircase.

The fort walls are perforated with numerous loopholes of different sizes to place heavy cannons. The parapet walls are crowned with merlons. The gateway is 2.1m wide and placed within a rectangle frame with a single turret with both outer sides on the north wall of the fort. It is set through a four-centred pointed archway and capped with merlons. The exterior of the gateway has panel decorations, and the interior has a plastered surface. The fort is entirely built with brick and mortar.

Location
The Lalbagh fort (originally termed as Quilla/ Fort Aurangabad) is located in the southern part of Dhaka city by the river Buriganga. The river has moved towards the south and now flows at quite a distance from the fort. The paintings of Charles D’Oily’s (1809-11) show that more than half of the south and south-eastern façade of the fort touched the river.

Description
The fort area covers 18 acres (73,00 sqm approximately) of land area. The fort principally contains three buildings within its premises: the mosque, the tomb of Iran Dukht (Bibi Pari), and the Dewan-i-Aam. Recent excavations have revealed the remains of several structures with elaborate arrangements for water supply, sewage, roof gardens and fountains.

Among the three surviving gateways, the southern one is the most impressive. The exterior provides the impression of a three-storied built form, whereas inside, it seems like a two-storied building. The gateway is bordered with slender minarets.

The central area of the fort comprises The Diwan-I Aam and the Hammam on the east, the mosque on the west and the tomb of Iran Dukht in between. All these buildings are placed within an axis, although not maintaining an equal distance. Water channels in both north-south and east-west direction with fountains placed at regular intervals connect the buildings, and a large square water tank at the west having 71.63m arms. The tank can be descended by four corner stairs.

The Diwan-i-Aam is a double-storeyed building with a single-storeyed Hammam attached to it on the west. The Hammam complex comprises an open platform, a small kitchen, an oven, water storage area, a masonry brick bathtub, a toilet, a dressing room and an extra room. The hammam also has an underground room for boiling water and a passage for sweepers.

The tomb of Bibi Pari consists of eight rooms surrounding a central square chamber containing the cenotaph of Iran Dukht. The chamber is roofed with a false octagonal dome wrapped in brass plate. The inner wall of the central room is finished entirely with white marble. The wall of the four corner rooms were skirted with glazed floral tiles of which only few original remains. The southeastern corner room contains a small grave of Shamsad Begum, possibly a relative of Bibi Pari. The mosque is a three-domed structure with a water tank on the eastern side for ablution.

The fortification wall on the south originally had five bastions at regular intervals, and the western wall had two bastions. The largest bastions among these seven is the one near the southern gateway at the back of the stable, which also has an underground tunnel. The central bastion of the southern wall is single-storeyed, and the rest are double-storeyed structures. The central one contains an underground room with verandah on three sides and can be approached either from the riverside or from its roof. The southwestern double-storeyed bastion was possibly a ‘Hawakhana’ with a water reservoir on its roof. All the establishments of the fort are connected with this reservoir using two terra-cotta pipes. A more robust terra-cotta dual terra-cotta pipeline, one inside the other, has been discovered in the area between the hammam and the tomb of Bibi Pari.

The northern side of the southern fortification used to have utility buildings such as the stable and the administrative block, whereas the western part accommodated a beautiful roof garden with arrangements for a fountain and a water reservoir. The residential part was located on the eastern side of the western fortification, mainly to the south-west of the mosque, where the remains of a sewerage line have been found. The southern fortification is a dual wall; the inner one is 13.72m high and 1.37m thick, and the outer wall is 6.10m high with the same thickness. There are openings at regular interval.

Justification of Outstanding Universal Value

Despite the geographic challenges of a riverine delta, the Mughals were adamant to conquer Bengal for its strategic and economic importance. In addition, they also had to develop naval forces to conduct an amphibious warfare against the local chieftains and pirates from Arakanese, Dutch and Portuguese origin. The Mughals struggled in their initial campaigns and eventually entered the Bengal only after adapting naval forces after being inspired from the local naval warfare techniques. After becoming the capital of Bengal Subah in 1610 CE, Dhaka still needed naval protection from the local adversaries and pirates until Shaista Khan conquered Chatgaon (Chottogram) in 1666 CE. Dhaka eventually became a major source of revenue for the Mughal empire as the capital of Bengal Subah and operational base for military campaigns in Assam region. The city became the trade centre for exporting various of local agricultural and craft products including the Muslin and virtually became the financial capital with a mint for producing coins.

The adjacent river courses enabled Dhaka to command all the major river routes of Bengal. The previous capital, Sonargaon lost its importance due the change of course of the surrounding rivers. Also, Islam Khan shifted the capital from Rajmahal to Dhaka, considering the strategic importance. Eventually, Dhaka replaced Sonargaon and Rajmahal in the process of becoming the capital of Bengal Subah for the next hundred years. The formation of forts at the key points of river routes to protect Dhaka thus signifies the value of the geographic location of the city.

The Mughals had to adapt with the riverine context for conducting warfare. From their adversaries, they learnt to mount the cannons on war-boats along with archers and matchlock men. Pirates from European origin were among one of the major foes of the Mughals. However, Portuguese men joined the Mughal Navy (Nawara) during the reign of Shaista Khan. The Mughal naval fleets Amla-e-Nawara and Amla-e-Assam were both based in Dhaka. They also adapted the local technique of reserving war-boats in canals adjacent to the important river confluences and deploying them in the river course for attacking after receiving signal from watch towers. The Mughals developed various kinds of war-boats using local ship building techniques and successfully engaged them against their enemies. They also found war-elephants to be effective in this climatic condition.

Although, the Mughals used to establish gigantic stone forts in the north-western part of Indian subcontinent, they found the Bengal delta devoid of stone as building material. The local adversaries on the other hand, used to rapidly construct smaller mud forts and engaged local boatmen to execute the construction in an inexpensive manner. Located strategically at important river confluences, these forts were significantly resilient against cannon shells and formed a combined defence instrument with the war-boats. The Mughals faced great difficulties in capturing these mud forts.

Highly influenced by these mud forts, the Mughals also placed their naval forts at important river confluences for defending Dhaka. Apart from being individually significant, the strategic location of the the Hajiganj fort, Sonakanda fort and Idrakpur fort along with their supportive establishments formed an integrated naval defence mechanism. Although, they constructed their forts and outposts with burnt brick and lime plaster, the platform of these forts, especially the artillery bases are elevated by filling up mud. The burnt bricks were also locally produced as stone was not readily available and would have involved greater expense and time. The mud artillery bases were also very effective for absorbing the reactive force of the cannons. The architectural details like bastions, gateways, archways, crenulations, merlon with loopholes etc. resembles Mughal character despite being smaller in size and scale.

After being secured by the naval forts, Dhaka became a major financial centre for Mughal economy. After the conquest of Chatgaon, Dhaka became secure from the Arakanese and Portuguese pirates. As a result, a palace fort complex was considered for the Subahdar of Bengal. Qila Aurangabad/ Lalbagh fort thus resembles all the constructional features of the previously built naval forts with some luxurious elements like marble and glazed floral tiles. The fort was also situated by the river Buriganga and although incomplete, contained a much complex layout than the naval forts. It also displays a compound water supply and sanitation layout.

Therefore, the Mughal forts of Dhaka can be attributed as the result of adaptation or reconfiguration in terms of architectural style to complement the fluvial terrain and landscape of Bengal and were crucial to secure the Provincial as well as the financial capital from which they generated almost half of their GDP. Although not very massive in size, the strategic placement considering the riverine landscape and the unique but hybrid characteristics coupled with distinctive naval forces made them very crucial for Dhaka for its inception as a capital city.

Criterion (ii): Although Bengal was prosperous with her various agricultural as well as crafts resources, Dhaka gained its first status as a provincial capital during the Mughal regime by a decree issued by emperor Jahangir and was given the name Jahangirnagar. The change of course of the river Meghna reduced the importance of the previous capital Sonargaon which also aided to select Dhaka as a strategically profound location by the Mughal rulers. Although it lost its status to Murshidabad in 1717 CE, the importance of its strategic advantage in terms of geopolitical and economic aspects was again felt in the event of dividing Bengal in 1905 CE during the British colonial period and was declared as the capital of Bengal and Assam. The status was again taken away in 1911 CE. After the independence from the British regime, Dhaka became the provincial capital of East Bengal, later renamed East Pakistan. After the independence of Bangladesh in 1971 CE from Pakistan, Dhaka became the capital city.

The Mughal subahdars operated their campaign against the local landlords, chieftains, Arakanese invaders, Portuguese pirates and later advanced towards Chatgaon and Ahom kingdom basing their centre on Dhaka. During the Mughal regime, Dhaka virtually became the financial capital of the empire producing a significant amount of per annum GDP even on a global scale. The window of trade and commerce for the European traders became open, and the exquisite products of Bengal began to be exported to the west.

The naval forts played a crucial role in establishing the Mughal regime in Bengal. They had to reconfigure their architectural and military knowledge to adapt to a relatively unknown fluvial network and deltaic landform. In appreciation of the efficiency of the local mud forts, which were very effective against artillery aggression and could be rapidly built by local people, they started to develop a unique type of naval forts which can be attributed as very endemic. The Mughals determined very strategic locations at the confluence of rivers also internally connected by numerous canals to establish the forts and erected naval forts. The forts at the key locations, which are the Hajiganj fort, the Sonakanda fort and the Idrakpur fort, were built with burnt brick and finished with lime plaster. The size and scale of the forts represents the key module which is burnt brick. As limestone or marble was not locally available, the Mughals selected relatively smaller burnt brick which was readily available due to the abundance of mud. The platforms of the forts, especially the artillery base were elevated with earth fill. Although, the key module for construction had to be adapted considering local context, the architectural features like walls, bastions, gateways, arches, merlons with loopholes, crenulations represent the Mughal architectural character. The use of plaster provides a monolithic texture to the overall form and the colour resembles the tone of red sandstone which was commonly used by the Mughals in Northern India.

The forts acted as a combined defence mechanism along with the Mughal Navy comprised of war-boats and matchlock men, which is also a unique phenomenon in the history of Mughal military strategy. The navy also included Portuguese mercenaries. The Naval force, along with infantry and cavalry, enabled the Mughals to develop an amphibian military force that eventually helped them command the Bengal delta and secure Dhaka, the capital of Subah-e-Bangla.

In contrast to the naval forts solely developed for defence, the Lalbagh fort was conceived as an administrative and residence for the subahdar of Bengal as well as a defence centre. However, the construction method followed the adaptive characteristics of the naval forts using the same materials and features. The arrangement was quite elaborate, which initially included the audience hall, a bathing facility, a mosque, and stables and barracks. The construction was held twice as Prince Azam had to go back to the Mughal capital Delhi to address the Maratha rebellion, and when Bibi Pari, the daughter of Subahdar Shaista Khan died in an untimely manner. Although incomplete, the Lalbagh fort represents the significance of Dhaka as the Mughal provincial capital.

Criterion (iv): The naval forts were solely built for protection, accumulation, dispersion, and mobilization of the military forces; hence, they did not contain any residential or recreational functions. To ensure proper surveillance, the bastions within the fortified walls, especially the ones facing the riverside became very prominent. The fortified walls, as well as the bastions, were not very high compared to the North Indian Mughal forts. The artillery base with storage facilities for gun powder is also a focal feature within the naval forts, especially in Sonakanda and Idrakpur fort. The loopholes at the merlons also accommodated the matchlock men to fire towards the river. Red sandstone and white marble, the traditional Mughal building materials, were not available in Bengal for which, they had to adapt Brick masonry along with lime mortar and plaster. The local construction technique with elevating the base with mud was adapted to build the fort rapidly. The doorways of the fort and to the artillery platforms display Mughal style archway.

Lalbagh Fort carries out a similar technique of fortification and construction technique, although the spatial arrangement was quite elaborate. The fort had various types of functions for the viceroy and the soldiers and included gardens at grade and rooftop decorated with water fountains. While the fortified wall at the south was built with the similar architectural features of the previously built naval forts, the rest of the fort had to incorporate a complex water supply infrastructure for the hammam (bath), the fountains and the roof garden using terra-cotta pipes. The sewage and drainage system are also very elaborate. The gateways represented several features of the Mughal architectural style. The tomb of Bibi Pari has limited use of marble stone finish and glazed coloured tiles that were profoundly used in North Indian Mughal buildings.

The Mughals essentially had to understand the nature of geography and landscape of the fluvial network and deltaic landform and eventually adapted with the local materials and techniques for warfare, financial venture and architecture. Although their venture in Bengal changed the course of Dhaka towards financial prosperity, which was ensured by securing the city from external enemies by means of these naval and administrative forts, the Mughals had to configure their style and practice according to the necessity of the nature of Bengal. The forts are the outcome of their struggle to conquer this unknown land for nearly two decades. The noteworthy feature is that these forts together formed a combined fortification which is unprecedented.

Statements of authenticity and/or integrity

Although temporarily used for various government organizations after the Mughal period, all the forts have been restored by the Department of Archaeology. Among the forts, only Idrakpur fort has several public residences within its boundary. All the forts are currently under the jurisdiction of Department of Archaeology, Ministry of Cultural Affairs, Government of the People’s Republic of Bangladesh.

As the rivers of Bengal continuously change their courses, currently, none of the forts has a river within its proximity. Due to siltation over a period of about 400 years, the rivers have shifted for about 1-2 km from its previous course during the Mughal period. The generated land around the fort is currently occupied with dense urban fabric. Although the view and landscape has been compromised, the forts can be perceived and identified as a heritage entity both from exterior and interior. The architectural remains have been very well preserved in terms of plan, form, material, and functional use.

Comparison with other similar properties

The Mughals developed a distinct Indo-Islamic architectural characteristic which can be described as an amalgamation of Islamic Persian, Turkic, and Indian traditions. The most notable Mughal buildings are in their capitals Delhi, Lahore, and Agra. Mughal buildings follow a very uniform pattern of structure and character, including large bulbous domes often surrounded by four smaller domes, slender minarets at the corners, massive halls, large, vaulted gateways and very delicate ornamentation. The buildings in these regions were mostly made with red sandstone and white marble. The components of large building complexes were planned following axial symmetry in an irregular manner. The precincts accommodated gardens and water bodies within them.

The Agra fort by the river Yamuna was built by Akbar the Great during 1564-1573 CE occupies an area of 94 acres (380,000 sqm) of land and has a semi-circular plan. The fort has double ramparts with massive circular bastions at intervals, battlements, embrasures, machicolations and string courses.

The fortified wall was almost seventy feet (21m) high. Four gates were provided on its four sides, one Khizri gate opening on to the river. The Agra fort was built over the ruins of a brick-built fort called Badalgarh. The fort was built with bricks in the inner core with sandstone on external surfaces. According to Abul Fazl, the fort contained five hundred buildings in the beautiful designs of Bengal and Gujarat. Some of them were demolished by Shah Jahan to replace them with his white marble palaces. The British troops of East India Company destroyed most of the others between 1803 and 1862 for raising barracks.

The Red fort was constructed by Mughal emperor Shah Jahan in 1639 CE as his fortified capital in Shahjahanabad. Occupying an area of 254.67 acres (1,030,611 sqm), the fort represents the supreme display of Mughal architecture which became very much refined under the supervision of Shah Jahan. The defensive walls have turrets and bastions at regular interval, and the height varies from 18m in the riverside to 33m in the cityside. The fort contained imperial apartments with a row of pavilions connected by a water channel known as the ‘stream of paradise’. The architectural details reflect a hybrid character of Islamic, Persian, Timurid and Hindu traditions. The innovative design of buildings and gardens within the fort influenced later architecture and landscape design in other regions. The marble, floral decoration, detailed screens and double domes display the pinnacle of Mughal architectural excellence.

Apart from these forts, Fatehpur Sikri and Lahore fort may also be mentioned to represent the imperial fortifications built in the North Indian region. The forts occupied a relatively large area and could function as a city. The strategy for fortification mainly addressed land-based aggressions despite being located by a river.

Compared to these forts located at the empire’s capital, the Mughal forts of Dhaka stand in quite a contrast. Red sandstone and white marble, the signature materials of Mughal architecture, had to be replaced with brick, lime mortar and lime plaster due to the unavailability of the stones in this region. Taking advantage of naturally higher terrain and the practice of building grand scale fortification to defend against attack from the land-based army became obsolete in the riverine delta. The Mughals had to focus on functionality and effectiveness rather than achieving precisions in terms of architectural marvels. In fact, the revenues from Subah-e-Bangla and the exquisite muslins contributed to the Mughal Empire to have the luxury to focus on architectural marvels, especially during the reign of Shah Jahan and Aurangzeb. The graceful ornamentation and decoration of the North Indian forts are absent. The Mughals had to adapt to the local geographic and landscape features along with naval warfare techniques of the local adversaries to operate warfare in both land and water. The naval fort and later on the Lalbagh fort, are thus a result of a reconfiguration of architectural characters considering the deltaic nature of the landscape and waterscape. Compared to the North Indian forts, the size of the naval forts as well as the Lalbagh Fort is quite small. Still, these forts were different in the sense that they worked holistically as a single system rather than being a single entity, which is unique. The Lalbagh fort displays the attempt to provide gardens and water channels representing paradise following the style of Shah Jahan. However, the construction technique for building and infrastructure follows the local tradition. The mosques, caravanserais and other buildings established by the Mughals in Dhaka and Bengal follow the same building materials as the forts, and the scale was not monumental as their North Indian counterparts.