a confederacy against the British, which, in addition to the French, included the Marathas and the Nizam of Hyderabad. War In July 1780 Hyder Ali invaded the Carnatic with an army of 80,000. He descended through the passes of the Eastern Ghats, burning villages as he went, before laying siege to British forts in northern Arcot. The British responded by sending a force of 5,000 to lift the sieges. From his camp at Arcot, Hyder Ali sent part of his army under the command of his eldest son, Tipu Sultan, to intercept a British force from Guntur, under the command of Colonel William Baillie, which had been sent to reinforce Colonel Hector Munro's army to the north at Madras. On the morning of 10 September 1780, Baillie's force came under heavy fire from Tipu's guns near Pollilur. Baillie formed his force into a long square formation and began to move slowly forward. However, Hyder Ali's cavalry broke through the formation's front, inflicting many casualties and forcing Baillie to surrender. Out of the British force of 3,820 men, 336 were killed. The defeat was considered to be the East India Company's most crushing loss in India up to that time. Munro reacted to the defeat by retreating to Madras, abandoning his baggage and dumping his cannons in the water tank at Kanchipuram, a small town some south of Madras. Naravane states in fact that it was a massacre with only 50 officers and 200 men taken prisoner, including Baille. Instead of following up the victory and pressing on for a decisive victory at Madras, Hyder Ali renewed the siege at Arcoty, which he captured on 3 November. This decision gave the British time to shore up their defences in the south, and to despatch reinforcements under the command of Sir Eyre Coote to Madras. Coote, though repulsed at Chidambaram, defeated Hyder Ali in succession in the battles of Porto Novo and Sholinghur, while Tipu was forced to raise the siege of Wandiwash, and besieged Vellore instead. The arrival of Lord Macartney as governor of Madras in the summer of 1781 included news of war with the Dutch Republic. Macartney ordered the seizure of Dutch outposts in India, and the British captured the main Dutch outpost at Negapatam after three weeks of siege in November 1781 against defenses that included 2,000 of Hyder Ali's men. This forced Hyder Ali to realize that