The 80th Carnatic Infantry were an infantry regiment of the British Indian Army. They could trace their origins to 1777, when they were raised as the 21st Carnatic Battalion, by enlisting men from the 2nd, the 6th, the 12th and the 15th Carnatic Battalions. The regiment's first action was during the Battle of Sholinghur in the Second Anglo-Mysore War. They also took part in the campaigns for the Third Anglo-Mysore War and were present at the Battle of Seringapatam in the Fourth Anglo-Mysore War in 1798. It was over 100 years before they were next called for active service during World War I.