The Revolutionary Socialist Party, initially known as the International Socialist Labour Party, was a political party

Political party

A political party is a political organization that typically seeks to influence government policy, usually by nominating their own candidates and trying to seat them in political office. Parties participate in electoral campaigns, educational outreach or protest actions...

 in Britain

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

. It emerged out of a Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

-based faction of the Socialist Labour Party, which had left the SLP in the early 1930s. The party was mainly based in Edinburgh

Edinburgh

Edinburgh is the capital city of Scotland, the second largest city in Scotland, and the eighth most populous in the United Kingdom. The City of Edinburgh Council governs one of Scotland's 32 local government council areas. The council area includes urban Edinburgh and a rural area...

, where it had its office and most of the party members lived. Members were also present in Glasgow

Glasgow

Glasgow is the largest city in Scotland and third most populous in the United Kingdom. The city is situated on the River Clyde in the country's west central lowlands...

, Aberdeen

Aberdeen

Aberdeen is Scotland's third most populous city, one of Scotland's 32 local government council areas and the United Kingdom's 25th most populous city, with an official population estimate of ....

 and Yorkshire

Yorkshire

Yorkshire is a historic county of northern England and the largest in the United Kingdom. Because of its great size in comparison to other English counties, functions have been increasingly undertaken over time by its subdivisions, which have also been subject to periodic reform...

. The party published The British Revolutionary Socialist.

RSP took part in conferences of the London Bureau as an observer. The party approached the Independent Labour Party

Independent Labour Party

The Independent Labour Party was a socialist political party in Britain established in 1893. The ILP was affiliated to the Labour Party from 1906 to 1932, when it voted to leave...

 about a merger in 1937, which the ILP rejected on the grounds that the RSP was under trotskyist

Trotskyism

Trotskyism is the theory of Marxism as advocated by Leon Trotsky. Trotsky considered himself an orthodox Marxist and Bolshevik-Leninist, arguing for the establishment of a vanguard party of the working-class...

 influence. The party then began orienting itself towards the Fourth International

Fourth International

The Fourth International is the communist international organisation consisting of followers of Leon Trotsky , with the declared dedicated goal of helping the working class bring about socialism...

.

The RSP was invited to and took part in the 'National Conference of Bolshevik-Leninists', held on July 30-July 31, 1938. Through this conference, the RSP merged into the Revolutionary Socialist League

Revolutionary Socialist League (UK, 1938)

The first RSL was formed in early 1938 with the merger of two different parties, the Marxist League led by Harry Wicks and the Marxist Group led by C. L. R. James....

.