Background
He was the older son of Henry Street Clair, 10th Lord Sinclair and his wife Grizel Cockburn, eldest daughter of Sir James Cockburn, 1st Baronet.
He was the older son of Henry Street Clair, 10th Lord Sinclair and his wife Grizel Cockburn, eldest daughter of Sir James Cockburn, 1st Baronet.
Street Clair was educated at the University of Franeker.
In 1708, he stood for Dysart Burghs to the British House of Commons, but as a peer"s eldest son, his election was declared void. Thereupon Street Clair joined Preston"s Regiment as a captain-lieutenant later in that year, however having killed two brothers in duels without seconds was forced to leave a short time after. Sentenced to death by a court martial, he was granted a reprieve by the regiment"s commander John Churchill, 1st Duke of Marlborough.
Street Clair came then in the service of King Frederick I of Prussia until being pardoned by Queen Anne of Great Britain in 1712.
In 1715, Street Clair supported the Jacobite rising and took part in the Battle of Sheriffmuir in November of that year, for which he was attainted and excluded from succession to his father"s lordship. He fled to Kirkwell Castle and therefrom to the continent.
Pardoned by letters patent in 1726, Street Clair returned to Scotland and although an act of parliament in 1736 relieved the forfeiture"s terms, he never assumed his title. She died in 1747 and Street Clair married secondly Amelia Murray, daughter of Lieutenant-General Lord George Murray at Arnhall on 24 April 1750.
Both his marriages were childless.
2nd Parliament of Great Britain.