The Battle of Plassey was a decisive victory of the British East India Company, under the leadership of Robert Clive, over the Nawab of Bengal and his French allies on 23 June 1757. The victory was made possible by the betrayal of Mir Jafar, Nawab Siraj-ud-Daulah's commander in chief, as well as much of the Bengal Subah's armies being earlier committed against an Afghan invasion led by Ahmad Shah Durrani against the Mughal Empire. The battle helped the British East India Company take complete control of Bengal in 1773. Over the next hundred years, they continued to expand their control over vast territories in the rest of the Indian subcontinent and Burma.
The battle took place at Palashi (Anglicised version: Plassey) on the banks of the Hooghly River, about 150 kilometres (93 mi) north of Calcutta (now Kolkata) and south of Murshidabad in West Bengal, then capital of Bengal State. The belligerents were the British East India Company and the Nawab Siraj-ud-Daulah, the last independent Nawab of Bengal. He succeeded Alivardi Khan (his maternal grandfather). Siraj-ud-Daulah had become the Nawab of Bengal the year before, and he had ordered the British to stop the extension of their fortification. Robert Clive bribed Mir Jafar, the commander-in-chief of the Nawab's army, and also promised to make him Nawab of Bengal. Clive defeated Siraj-ud-Daulah at Plassey in 1757 and captured Calcutta.
The battle was preceded by an attack on British-controlled Calcutta by Nawab Siraj-ud-Daulah and the Black Hole massacre. The British sent reinforcements under Colonel Robert Clive and Admiral Charles Watson from Madras to Bengal and recaptured Calcutta. Clive then seized the initiative to capture the French fort of Chandannagar. Tensions and suspicions between Siraj-ud-daulah and the British culminated in the Battle of Plassey. The battle was waged during the Seven Years' War (1756–1763), and, in a mirror of their European rivalry, the French East India Company (La Compagnie des Indes Orientales) sent a small contingent to fight against the British. Siraj-ud-Daulah had a vast numerically superior force and made his stand at Plassey. The British, worried about being outnumbered, formed a conspiracy with Siraj-ud-Daulah's demoted army chief Mir Jafar, along with others such as Yar Lutuf Khan, Jagat Seths (Mahtab Chand and Swarup Chand), Umichand and Rai Durlabh. Mir Jafar, Rai Durlabh and Yar Lutuf Khan thus assembled their troops near the battlefield but made no move to actually join the battle. Siraj-ud-Daulah's army, with about 50,000 soldiers (including defectors), 40 cannons and 10 war elephants, was defeated by 3,000 soldiers of Col. Robert Clive, owing to the flight of Siraj-ud-Daulah from the battlefield and the inactivity of the conspirators. The battle ended in approximately 11 hours.
This is judged to be one of the pivotal battles in the control of the Indian subcontinent by the colonial powers. The British now had a great deal of wealth and influence over the Nawab—Mir Jafar, and as a result, they were able to get important concessions for earlier losses and trade income. The British further used this revenue to increase their military might and push the other European colonial powers, such as the Dutch and the French, out of South Asia, thus expanding the British Empire.
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. 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. It made the Nawab of Bengal a tributary to the Marathas, who agreed to pay Rs. 1.2 million annually as the chauth of Bengal and Bihar, and the Marathas agreed not to invade Bengal again. The Nawab of Bengal also paid Rs. 3.2 million to the Marathas towards the arrears of chauth for the preceding years.
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 latecomers in Indian trade, but they quickly established themselves in India and were poised to overtake Britain for control.
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 for 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.
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.
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 were 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.