William Wolfe (more commonly referred to as Billy Wolfe) is a former leader of the Scottish National Party (SNP). Wolfe was born in February 1924 and after serving in the British Army in the Second World War he became active in various organisations designed to highlight the distinctiveness of Scotland and Scottish culture in particular. He began to believe though that only through direct political action would Scotland be advanced and became convinced of the need for Scottish independence. So in 1959 he joined the SNP.

He stood as the SNP candidate in the 1962 West Lothian by-election against Tam Dalyell polling very well and managing to come second in a seat where previously the SNP had made little impact. He became aware of the need for greater professionalism in the organisation of the SNP and diverted his attentions to this matter thereafter.

In 1969 he replaced Arthur Donaldson as SNP National Convenor, and it was during Wolfe's period as leader that the party had its greatest electoral success to the Westminster parliament, winning 11 seats in the October '74 General Election. It is also Wolfe that is credited with doing much to develop the SNP as a clearly defined left-of-centre political party.

In 1979 he stood down as SNP leader to be replaced by Gordon Wilson. He has remained active in the SNP as well as the Campaign for Nuclear Disarmament.

Wolfe wrote a book that was part autobiography, and part polemic entitled Scotland Lives: the Quest for Independence. It was published in 1971.