St Clair was born in
Gibraltar in 1785 where his father, William, was a colonel of the
"Scottish Borderers" – the 25th regiment. St Clair's childhood was spent in Scotland at
Rosslyn Castle where his father was employed by the
first Earl of Rosslyn. Thomas had an elder brother called William who was involved with the mutiny in Gibraltar. William died fighting in
Martinique in 1809. He also had a brother David and two sisters. His father was a friend of
Prince Edward, Duke of Kent and Strathearn and he was able to use this to advance his career more rapidly. In the summer of 1809 he took part in the
Walcheren Campaign in the
Netherlands. In 1814 he was awarded an
Army Gold Medal for his part in the
Battle of the Nive. By 21 June 1817 he was a lieutenant colonel. In 1820, St. Clair returned to the
Rock of Gibraltar as one of the senior officers in command of the garrison at the age of just 36. In 1832 he was sent to Malta and in 1834 he published his autobiographical book
A Soldiers Recollections of the West Indies and America. St. Clair died in
Malta in 1847 a year after he was made a major-general. ==Legacy==