The regiment was raised in Scotland by Thomas Graham as the 90th Regiment of Foot, in response to the threat posed by the French Revolution, on 10 February 1794. Graham was given permission to uniform and drill his regiment as a light infantry battalion. It embarked as part of the Quiberon Expedition and took part in the capture of the Île d'Yeu in September 1795. The following year the regiment was dispatched to support the French Royalist Lieutenant-general François de Charette in his struggle with the Republicans. It took part in the Capture of Minorca in November 1798 and then sailed for Malta in November 1800 before transferring to Egypt in March 1801 for service in the Egyptian Campaign. It saw action at the Battle of Abukir on 8 March 1801 and the Battle of Mandora on 13 March 1801 before returning to Malta in September 1801 and sailing for England in February 1802.