Archibald Sinclair, 1st Viscount Thurso (then Sir Archibald Sinclair) was leader of the UK Liberal Party from 1935 until 1945.
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|width="30%" align="center"|Preceded by:
New creation
|width="40%" align="center"|Viscount Thurso
|width="30%" align="center"|Followed by:
Robin MacDonald Sinclair
|}