The regiment's commanding officer was William Pollock, who had seen active service in the Siege of Fort St. Philip on Minorca during the American Revolutionary War, becoming a prisoner of war after the siege. He then served in Ireland and England between 1782 and 1792 before being sent to Gibraltar and participating in the Toulon. Service in the Mediterranean followed, in Corsica and Portugal in 1797. After this, he was sent to the East Indies, before returning to Ireland on recruiting duty during 1806 in the run up to the 101st Foot being established. Pollock was assisted in the recruitment by Major George O'Malley. O'Malley commanded the unit during its deployment overseas, but wanted to serve in Europe, a wish that was granted in 1815 when he became the commander of the 2nd battalion of 44th Regiment of Foot at the Battle of Waterloo.