The Battle of Pollilur, also known as the Battle of Polilore or Battle of Perambakam, took place on 10 September 1780 at Pollilur near the city of Kanchipuram in present-day Tamil Nadu state, India as part of the Second Anglo-Mysore War. It was waged between two forces commanded by Tipu Sultan of the Kingdom of Mysore, and Colonel William Baille of the British East India Company. The army of the East India Company surrendered and suffered a high number of casualties. It was the worst loss the British suffered on the subcontinent until Chillianwala. https://en.wikipedia.org/wiki/Battle_of_Pollilur_(1780)
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Mysorean rockets were the first iron-cased rockets successfully deployed for military use. Hyder Ali, the 18th century ruler of Mysore, and his son and successor, Tipu Sultan used them effectively against the British East India Company during the 1780s and 1790s. Their conflicts with the company exposed the British to this technology, which was then used to advance European rocketry with the development of the Congreve rocket in 1805 https://en.wikipedia.org/wiki/Mysorean_rockets
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