He was raised to the title of Marquess Cornwallis in 1792 as recognition for his performance in the Third Anglo-Mysore War, in which he extracted significant concessions from the Mysorean ruler, Tipu Sultan. Returned to England in 1793, he was engaged in administrative and diplomatic postings until 1798, when he was posted to the Kingdom of Ireland as Lord Lieutenant and Commander-in-Chief. In 1801, he was again posted to India. He arrived in July 1805 and died in October in Ghazipur.