Archibald Sinclair was the Liberal leader from 1935 to 1945. He was a leading figure in British politics in that period, first as an outspoken critic of appeasement, and then as a minister during the war. For Liberals, his importance lay in his belief in the possibility of a Liberal revival, which was crucial in helping the party to survive the challenges of the 1930s and 1940s.
Archibald Henry Macdonald Sinclair, fourth baronet and first Viscount Thurso of Ulbster, was born in London on 22 October 1890. Educated at Eton, he attended Sandhurst, and became a regular soldier in 1910 with the 2nd Life Guards. Serving with distinction on the Western Front throughout the Great War, he was Winston Churchill’s second-in-command with the 6th Royal Scots Fusiliers from January to May 1916, and ended the war as a major in the Guards Machine-Gun Regiment. In 1919-21, he was Churchill’s personal military secretary at the War Office, and was then his private secretary at the Colonial Office until 1922. At the 1922 general election, Sinclair successfully stood as a pro-Lloyd George National Liberal in Caithness & Sutherland. In each election until 1945 (when he lost the seat), and in 1950, he stood as a Liberal.
Sinclair soon became a prominent figure on the opposition benches, assisting Lloyd George with revisions of Liberal policy from the mid-1920s. He was a founder member of the Land Committee, and chaired its Scottish equivalent, which wrote the Liberal ‘Tartan Book’ proposing Scottish devolution. In November 1930, he became Liberal Chief Whip in the House of Commons, making the maintenance of party discipline and unity his highest priority. In 1931 he took part (with Lloyd George, Samuel, and Lothian) in talks with the Labour leadership over various areas of shared interest. This meant that he was an obvious choice as one of the Liberal ministers in the National Government from August 1931, when he ceased to be Chief Whip.
Sinclair served as Secretary of State for Scotland from August 1931 to September 1932, with Cabinet rank from November 1931. The main battle for the Liberals in the National Government was for free trade, and after agreeing to differ with their Labour and Conservative colleagues over minor tariffs in January 1932, the Liberals eventually resigned from the government in September 1932, when extensive tariffs were introduced under the Ottawa Agreements. Samuel had replaced Lloyd George as Liberal Leader after the 1931 general election and, when Samuel lost his seat in the November 1935 election, Sinclair replaced him.
From then until 1939, Sinclair’s leadership was marked by two themes. Firstly, he was a resolute proponent of Liberal independence, vigorously pushing the Liberal viewpoint in Parliament and throughout the country, persistently believing that the Liberal Party was about to make an electoral breakthrough. Secondly, Sinclair opposed appeasement, wanting instead to pursue a policy of collective security. This involved developing the League of Nations ability to remedy just grievances, while at the same time rearming so that League members could resist aggression. He accepted that Germany and the other expansionist powers had legitimate complaints, but he wanted them dealt with from a position of strength and through international negotiations, rather than by the government’s piecemeal concessions to the dictators. Sinclair cooperated with members of all parties in support of the League, including Churchill and Attlee, through the Arms and the Covenant movement. However, their message was often at odds with what most British people wanted to hear, and Sinclair and the other anti-appeasers were constantly denounced as warmongers.
When war broke out in September 1939, Sinclair was invited to join the government by Neville Chamberlain, but he demurred. However, when a broad coalition government was constructed under Churchill in May 1940, Sinclair accepted the post of Secretary of State for Air, holding the post until the coalition broke up in May 1945. Sinclair did not gain a War Cabinet seat, but Churchill agreed to consult him on general issues and principles. Sinclair’s influence within the government was questionable and even at the Air Ministry he was weakened by Churchill taking a prominent role in decision-making himself, but Sinclair was important in supporting Arthur ‘Bomber’ Harris’s strategic bombing of Germany. Sinclair believed that it was an effective way of destroying Germany’s war effort and morale and maintained that targets were industrial rather than residential.
Party campaigns were effectively suspended on the outbreak of war, and Sinclair strongly believed that military victory was the main priority. This meant, for example, that he did not campaign vigorously for the Beveridge Report, which had provoked much enthusiasm within the Liberal Party and the country, but was put aside until after the war by the coalition government. After pressure from party members he did commit the Party to contest the post-war general election as an independent entity, but he personally favoured the continuation of coalition long after the war. With the war in Europe won, the general election took place in July 1945, and the Liberals did poorly, winning only twelve seats. Sinclair himself lost his seat, and was replaced as leader by Clement Davies. The change was intended to be temporary following a rash promise by Sinclair’s Conservative opponent to resign his seat in Sinclair’s favour if he won. Needless to say, the promise went unfulfilled.
Sinclair again stood unsuccessfully for Parliament in 1950 and after the 1951 election there were rumours that Churchill wished to bring him into his Cabinet. When Sinclair became Viscount Thurso in 1952, it was intended that he would lead the Liberals in the House of Lords, but a stroke prevented him from taking an active part there until 1954. Outside Liberal politics, Sinclair was Lord Lieutenant of Caithness (1919-64); Lord Rector of Glasgow University (1938-45); President of the Air League of the British Empire (1956-58); and a member of the Political Honours Scrutiny Committee (1954-61).
A second stroke, in 1959, meant that he was severely debilitated in his last years, and he died on 15 June 1970 at his home in Twickenham. Sinclair had become Fourth Baronet of Ulbster in 1912, a Companion of the Order of St. Michael and St. George in 1922, and a Knight of the Order of the Thistle in 1941. He married Marigold Forbes (died 1975) in 1918; they had two sons (Robin and Angus) and two daughters (Catherine and Elizabeth). Sinclair wrote no books or memoirs, although a number of his speeches were published as pamphlets. There is one short biography: Gerard J. De Groot, Liberal Crusader: The Life of Sir Archibald Sinclair (1992).
 
Richard Grayson is Director of Policy of the Liberal Democrats and the chief policy adviser to the party leader. He is the author of Austen Chamberlain and the Commitment to Europe: British Foreign Policy, 1924-29 (1997) and Liberals, International Relations and Appeasement: The Liberal Party, 1919-39 (2001).