<P> 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 defences 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 Muhammed 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 . </P> <P> 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 Mohammed Ali's last stronghold Trichinopoly, where Ali was holed up with his British reinforcements . He was aided by a French force under Charles, Marquis de Bussy . </P> <P> 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 Mohammed Ali 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 Mohammed Ali succeeded to the throne of the Nawab in accordance with a treaty with the new French governor Godeheu . </P> <P> 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 his wars with the Marathas, 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 . 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 . </P>

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