Archibald Sinclair, 1st Viscount Thurso
Archibald Henry Macdonald Sinclair, 1st Viscount Thurso (then Sir Archibald Sinclair) was leader of the UK Liberal Party from 1935 until 1945.Sinclair served on the Western Front during the First World War and rose to the position of major in the Guards Machine-Gun Regiment.
In 1922 he entered the House of Commons as a Liberal MP for Caithness & Sutherland supporting David Lloyd George, defeating the incumbant supporter of Herbert Henry Asquith. He rose through the Liberal ranks as the party shrank in Parliament, becoming Chief Whip by 1930. In 1931 the Liberal Party joined the National Government of Ramsay MacDonald and Sinclair held the post of Secretary of State for Scotland. The following year he, together with other Liberal ministers, resigned from the government in protest at the Ottawa Convention introducing a series of tariff agreements. Sinclair and the Liberal leader, Sir Herbert Samuel, were thus the last Liberal politicians to sit in the Cabinet.
In the 1935 general election, Samuel lost his seat. Sinclair became the party's leader at the head of only twenty MPs. With the party now clearly marginalised as a third party on the fringe, he fought to rebuild it, taking up the issues of opposition to the continental dictatorships and working worked closely with Winston Churchill who was a backbencher at that time and generally shunned by his Conservative Party. When Churchill formed an all-party coalition government in 1940, Sinclair became Secretary of State for Air. However he did not sit in the small War Cabinet, though he was invited to attend meetings discussing any political matter. He remained a minister until May 1945 when the coalition ended. In the 1945 general election, he narrowly lost his seat. There was speculation that he might return to the Commons and the leadership, but he was unsuccessful in his attempt to re-enter Parliament in 1950. In 1952 he accepted elevation to the House of Lords as Viscount Thurso.
In the 1990s, his grandson, John Thurso entered politics and now sits as MP for Caithness, Sutherland & Easter Ross.
| Preceded by: William Adamson | Secretary of State for Scotland 1931-1932 | Followed by: Sir Godfrey Collins |
| Preceded by: Sir Samuel Hoare | Secretary of State for Air 1940-1945 | Followed by: Harold Macmillan |
| Preceded by: Sir Herbert Samuel | Leader of the British Liberal Party 1935-1945 | Followed by: Clement Davies |
| Preceded by: New creation | Viscount Thurso | Followed by: Robin MacDonald Sinclair |