The Bengal Subah; also referred to as the Mughal Bengal, was the largest subdivision of the Mughal Empire and later an independent state under the Nawab of Bengal encompassing much of the Bengal region, which includes modern Bangladesh and the Indian state of West Bengal, between the 16th and 18th centuries.^{[citation needed]} From 1741 to 1751, the Marathas under Raghuji Bhonsle invaded Bengal six times. In 1751, the Marathas signed a peace treaty with the Nawab of Bengal, according to which Mir Habib (a former courtier of Alivardi Khan, who had defected to the Marathas) was made provincial governor of Orissa under nominal control of the Nawab of Bengal.^[4] It made The Nawab of Bengal a tributary to the Marathas who agrees to pay Rs. 1.2 million annually as the chauth of Bengal and Bihar, and the Marathas agreed not to invade Bengal again.^[5][6] The Nawab of Bengal also paid Rs. 3.2 million to the Marathas, towards the arrears of chauth for the preceding years.^[7]

The British East India Company had a strong presence in India with its three main stations of Fort St. George in Madras, Fort William in Calcutta, and Bombay Castle in western India since the Anglo-Mughal War. These stations were independent presidencies governed by a president and a council, appointed by the Court of Directors in England. The British adopted a policy of allying themselves with various princes and Nawabs, promising security against usurpers and rebels. The Nawabs often gave them concessions in return for the security.

By the 18th century all rivalry had ceased between the British East India Company and the Dutch or Portuguese counterparts. The French had also established an East India Company under Louis XIV and had two important stations in India – Chandernagar in Bengal and Pondicherry (now Puducherry district) on the Carnatic coast, both governed by the presidency of Pondicherry. The French were a late comer in India trade, but they quickly established themselves in India and were poised to overtake Britain for control.^[8][9]

The War of the Austrian Succession (1740–1748) marked the beginning of the power struggle between Britain and France and of European military ascendancy and political intervention in the Indian subcontinent. In September 1746, Mahé de La Bourdonnais landed off Madras with a naval squadron and laid siege to the port city. The defenses of Madras were weak and the garrison sustained a bombardment of three days before surrendering. The terms of the surrender agreed by Bourdonnais provided for the settlement to be ransomed back for a cash payment by the British East India Company. However, this concession was opposed by Joseph François Dupleix, the governor general of the Indian possessions of the Compagnie des Indes Orientales. When Bourdonnais left India in October, Dupleix reneged on the agreement. The Nawab of the Carnatic Anwaruddin Khan intervened in support of the British and the combined forces advanced to retake Madras, but despite vast superiority in numbers, the army was easily crushed by the French. As retaliation to the loss of Madras, the British, under Major Lawrence and Admiral Boscawen, laid siege to Pondicherry but were forced to raise it after thirty-one days. The Treaty of Aix-la-Chapelle in 1748 forced Dupleix to yield Madras back to the British in return for Louisbourg and Cape Breton Island in North America.^[8][10]

The Treaty of Aix-La-Chapelle prevented direct hostilities between the two powers but soon they were involved in indirect hostilities as the auxiliaries of the local princes in their feuds. The feud Dupleix chose was for the succession to the positions of the Nizam of the Deccan and the Nawab of the dependent Carnatic province. The British and the French both nominated their candidates for the two posts. In both cases, Dupleix’s candidates usurped both thrones by manipulation and two assassinations. In mid-1751, the French candidate for the Nawab’s post, Chanda Sahib, laid siege to the British candidate Wallajah’s last stronghold Trichinopoly, where Wallajah was holed up with his British reinforcements. He was aided by a French force under Charles, Marquis de Bussy.^[8][11]

On 1 September 1751, 280 Europeans and 300 sepoys under the command of Captain Robert Clive attacked and seized Arcot, the capital of the Carnatic, finding that the garrison had fled the night before. It was hoped that this would force Chanda Sahib to divert some of his troops to wrest the city back from the British. Chanda Sahib sent a force of 4,000 Indians under Raza Sahib and 150 Frenchmen. They besieged the fort and breached the walls in various places after several weeks. Clive sent out a message to Morari Rao, a Maratha chieftain who had received a subsidy to assist Wallajah and was encamped in the Mysore hills. Raza Sahib, learning of the imminent Maratha approach, sent a letter to Clive asking him to surrender in return for a large sum of money but this offer was refused. In the morning of 24 November, Raza Sahib tried to mount a final assault on the fort but was foiled in his attempt when his armoured elephants stampeded due to the British musketry. They tried to enter the fort through the breach several times but always repulsed with loss. The siege was raised the next day and Raza Sahib’s forces fled from the scene, abandoning guns, ammunition and stores. With success at Arcot, Conjeeveram and Trichinopoly, the British secured the Carnatic and Wallajah succeeded to the throne of the Nawab in accordance with a treaty with the new French governor Godeheu.^[12][13]

Alwardi Khan ascended to the throne of the Nawab of Bengal after his army attacked and captured the capital of Bengal, Murshidabad. Alivardi’s attitude to the Europeans in Bengal is said to be strict. During the Maratha invasions of Bengal, he allowed the strengthening of fortifications by the Europeans and the construction of the Maratha Ditch in Calcutta by the British. On the other hand, he collected large amounts of money from them for the upkeep of his war.^{[citation needed]} He was well-informed of the situation in southern India, where the British and the French had started a proxy war using the local princes and rulers. Alwardi did not wish such a situation to transpire in his province and thus exercised caution in his dealings with the Europeans. However, there was continual friction; the British always complained that they were prevented from the full enjoyment of the farman of 1717 issued by Farrukhsiyar. The British, however, protected subjects of the Nawab, gave passes to native traders to trade custom-free and levied large duties on goods coming to their districts – actions which were detrimental to the Nawab’s revenue.^[14]

In April 1756, Alwardi Khan died and was succeeded by his twenty-three-year-old grandson, Siraj-ud-daulah. His personality was said to be a combination of a ferocious temper and a feeble understanding. He was particularly suspicious of the large profits made by the European companies in India. When the British and the French started improving their fortifications in anticipation of another war between them, he immediately ordered them to stop such activities as they had been done without permission.^[15] When the British refused to cease their constructions, the Nawab led a detachment of 3,000 men to surround the fort and factory of Cossimbazar and took several British officials as prisoners, before moving to Calcutta.^[16] The defences of Calcutta were weak and negligible. The garrison consisted of only 180 soldiers, 50 European volunteers, 60 European militia, 150 Armenian and Portuguese militia, 35 European artillery-men and 40 volunteers from ships and was pitted against the Nawab’s force of nearly 50,000 infantry and cavalry. The city was occupied on 16 June by Siraj’s force and the fort surrendered after a brief siege on 20 June.^{[17][18][19][20][21]}

The prisoners who were captured at the siege of Calcutta were transferred by Siraj to the care of the officers of his guard, who confined them to the common dungeon of Fort William known as The Black Hole. This dungeon, 18 by 14 feet (5.5 m × 4.3 m) in size with two small windows and originally employed by the British to hold only six prisoners, had 146 prisoners thrust into it. On 21 June, the doors of the dungeon were opened and only 23 of the 146 walked out, the rest died of asphyxiation, heat exhaustion and delirium.^[22] It appears that the Nawab was unaware of the conditions in which his prisoners were held which resulted in the unfortunate deaths of most of the prisoners. Meanwhile, the Nawab’s army and navy were busy plundering the city of Calcutta and the other British factories in the surrounding areas.^{[23][24][25][26]}

When news of the fall of Calcutta broke in Madras on 16 August 1756, the Council immediately sent out an expeditionary force under Colonel Clive and Admiral Watson. A letter from the Council of Fort St. George, states that “the object of the expedition was not merely to re-establish the British settlements in Bengal, but also to obtain ample recognition of the Company’s privileges and reparation for its losses” without the risk of war. It also states that any signs of dissatisfaction and ambition among the Nawab’s subjects must be supported.^[27] Clive assumed command of the land forces, consisting of 900 Europeans and 1500 sepoys while Watson commanded a naval squadron. The fleet entered the Hooghly River in December and met with the fugitives of Calcutta and the surrounding areas, including the principal members of the council, at the village of Falta on 15 December. The members of council formed a Select Committee of direction. On 29 December, the force dislodged the enemy from the fort of Budge Budge. Clive and Watson then moved against Calcutta on 2 January 1757 and the garrison of 500 men surrendered after offering a scanty resistance.^[28] With Calcutta recaptured, the council was reinstated and a plan of action against the Nawab was prepared. The fortifications of Fort William were strengthened and a defensive position was prepared in the north-east of the city.^[29][26][30]

On 9 January 1757, a force of 650 men under Captain Coote and Major Kilpatrick stormed and sacked the town of Hooghly, 23 miles (37 km) north of Calcutta.^[31] On learning of this attack, the Nawab raised his army and marched on Calcutta, arriving with the main body on 3 February and encamping beyond the Maratha Ditch. Siraj set up his headquarters in Omichund’s garden. A small body of their army attacked the northern suburbs of the town but were beaten back by a detachment under Lieutenant Lebeaume placed there, returning with fifty prisoners.^{[32][33][34][35][36]}

Clive decided to launch a surprise attack on the Nawab’s camp on the morning of 4 February. At midnight, a force of 600 sailors, a battalion of 650 Europeans, 100 artillerymen, 800 sepoys and 6 six-pounders approached the Nawab’s camp. At 6:00, under the cover of a thick fog, the vanguard came upon the Nawab’s advanced guard, who after firing with their matchlocks and rockets, ran away. They continued forward for some distance until they were opposite Omichund’s garden, when they heard the galloping of cavalry on their right. The cavalry came within 30 yards (27 m) of the British force before the line gave fire, killing many and dispersing the rest. The fog hampered visibility beyond walking distance. Hence, the line moved slowly, infantry and artillery firing on either side randomly. Clive had intended to use a narrow raised causeway, south of the garden, to attack the Nawab’s quarters in the garden. The Nawab’s troops had barricaded the passage. At about 9:00, as the fog began to lift, the troops were overwhelmed by the discharge of two pieces of heavy cannon from across the Maratha Ditch by the Nawab’s artillery. The British troops were assailed on all sides by cavalry and musket-fire. The Nawab troops then made for a bridge a mile further on, crossed the Maratha Ditch and reached Calcutta. The total casualties of Clive’s force were 57 killed and 137 wounded. The Nawab’s army lost 22 officers of distinction, 600 common men, 4 elephants, 500 horses, some camels and a great number of bullocks. The attack scared the Nawab into concluding the Treaty of Alinagar with the Company on 9 February, agreeing to restore the Company’s factories, allow the fortification of Calcutta and restoring former privileges. The Nawab withdrew his army back to his capital, Murshidabad.^{[37][38][39][40][41]}

Concerned by the approach of de Bussy to Bengal and the Seven Years’ War in Europe, the Company turned its attention to the French threat in Bengal. Clive planned to capture the French town of Chandannagar, 20 miles (32 km) north of Calcutta. Clive needed to know whose side the Nawab would intervene on if he attacked Chandannagar. The Nawab sent evasive replies and Clive construed this to be assent to the attack.^[42] Clive commenced hostilities on the town and fort of Chandannagar on 14 March. The French had set up defences on the roads leading to the fort and had sunk several ships in the river channel to prevent passage of the men of war. The garrison consisted of 600 Europeans and 300 sepoys. The French expected assistance from the Nawab’s forces from Hooghly, but the governor of Hooghly, Nandkumar had been bribed to remain inactive and prevent the Nawab’s reinforcement of Chandannagar. The fort was well-defended, but when Admiral Watson’s squadron forced the blockade in the channel on 23 March, a fierce cannonade ensued with aid from two batteries on the shore. The naval squadron suffered greatly due to musket-fire from the fort. At 9:00 on 24 March, a flag of truce was shown by the French and by 15:00, the capitulation concluded. After plundering Chandannagar, Clive decided to ignore his orders to return to Madras and remain in Bengal. He moved his army to the north of the town of Hooghly.

The Nawab was infuriated on learning of the attack on Chandernagar. His former hatred of the British returned, but he now felt the need to strengthen himself by alliances against the British. The Nawab was plagued by fear of attack from the north by the Afghans under Ahmad Shah Durrani and from the west by the Marathas. Therefore, he could not deploy his entire force against the British for fear of being attacked from the flanks. A deep distrust set in between the British and the Nawab. As a result, Siraj started secret negotiations with Jean Law, chief of the French factory at Cossimbazar, and de Bussy. The Nawab also moved a large division of his army under Rai Durlabh to Plassey, on the island of Cossimbazar 30 miles (48 km) south of Murshidabad.^{[39][47][48][49]}

Popular discontent against the Nawab flourished in his own court. The Seths, the traders of Bengal, were in perpetual fear for their wealth under the reign of Siraj, contrary to the situation under Alivardi’s reign. They had engaged Yar Lutuf Khan to defend them in case they were threatened in any way.^[50] William Watts, the Company representative at the court of Siraj, informed Clive about a conspiracy at the court to overthrow the ruler. The conspirators included Mir Jafar, paymaster of the army, Rai Durlabh, Yar Lutuf Khan and Omichund, a merchant and several officers in the army.^[51] Invited by Mir Jafar to join the conspiracy, Clive referred the matter to a committee of senior Company officials. By 1 May, the committee passed a resolution in support of the alliance. A treaty was signed between the British and Mir Jafar agreeing, in return for substantial financial incentives, to help him overthrow the Nawab. According to historian W. Dalrymple, the Jagat Seths offered Clive and the East India Company more than £4m (£420m as of 2019), an additional 110,000 rupees a month (£1.43m as of 2019) to pay for Company troops, and other landholding rights.^[52] On 2 May, Clive broke up his camp and sent half the troops to Calcutta and the other half to Chandernagar.^{[53][54][55][56]}

Mir Jafar and the Seths desired that the confederacy between the British and himself be kept secret from Omichund, but when he found out about it, he threatened to betray the conspiracy if his share was not increased to three million rupees (£300,000, which would be over £3m in 2019). Hearing of this, Clive suggested an expedient to the committee. He suggested that two treaties be drawn – the real one on white paper, containing no reference to Omichund and the other on red paper, containing Omichund’s desired stipulation, to deceive him. The members of the committee signed on both treaties, but Admiral Watson signed only the real one and his signature had to be counterfeited on the fictitious one.^[57] Both treaties and separate articles for donations to the army, navy squadron and committee were signed by Mir Jafar on 4 June.^[58][59

Clive testified and defended himself thus before the House of Commons of Parliament on 10 May 1773, during the Parliamentary inquiry into his conduct in India:

Omichund, his confidential servant, as he thought, told his master of an agreement made between the English and Monsieur Duprée [may be a mistranscription of Dupleix] to attack him, and received for that advice a sum of not less than four lacks of rupees. Finding this to be the man in whom the nabob entirely trusted, it soon became our object to consider him as a most material engine in the intended revolution. We therefore made such an agreement as was necessary for the purpose, and entered into a treaty with him to satisfy his demands. When all things were prepared, and the evening of the event was appointed, Omichund informed Mr. Watts, who was at the court of the nabob, that he insisted upon thirty lacks of rupees, and five per cent. upon all the treasure that should be found; that, unless that was immediately complied with, he would disclose the whole to the nabob; and that Mr. Watts, and the two other English gentlemen then at the court, should be cut off before the morning. Mr. Watts, immediately on this information, dispatched an express to me at the council. I did not hesitate to find out a stratagem to save the lives of these people, and secure success to the intended event. For this purpose we signed another treaty. The one was called the Red, the other the White treaty. This treaty was signed by every one, except admiral Watson; and I should have considered myself sufficiently authorised to put his name to it, by the conversation I had with him. As to the person who signed admiral Watson’s name to the treaty, whether he did it in his presence or not, I cannot say; but this I know, that he thought he had sufficient authority for so doing. This treaty was immediately sent to Omichund, who did not suspect the stratagem. The event took place, and success attended it; and the House, I am fully persuaded, will agree with me, that, when the very existence of the Company was at stake, and the lives of these people so precariously situated, and so certain of being destroyed, it was a matter of true policy and of justice to deceive so great a villain.