The following is a list of Trotskyist organizations by country. This article lists only those currently existing parties which self-identify ideologically as Trotskyist. Included are Trotskyist factions, but not youth organizations or party alliances.
Trotskyism is the political ideology and branch of Marxism developed by Russian revolutionary and intellectual Leon Trotsky along with some other members of the Left Opposition and the Fourth International. Trotsky described himself as an orthodox Marxist, a revolutionary Marxist, and a Bolshevik–Leninist as well as a follower of Karl Marx, Frederick Engels, Vladimir Lenin, Karl Liebknecht, and Rosa Luxemburg. His relations with Lenin have been a source of intense historical debate. However, on balance, scholarly opinion among a range of prominent historians and political scientists such as E.H. Carr, Isaac Deutscher, Moshe Lewin, Ronald Suny, Richard B. Day and W. Bruce Lincoln was that Lenin’s desired “heir” would have been a collective responsibility in which Trotsky was placed in "an important role and within which Stalin would be dramatically demoted ".
The Fourth International (FI) was a political international established in France in 1938 by Leon Trotsky and his supporters, having been expelled from the Soviet Union and the Communist International.
The Trotskyist Fraction – Fourth International (TF-FI) is a political international of Trotskyist political organizations that claim to adhere to the political legacy of the Fourth International.
James Robertson (1928–2019) was the long-time and founding National Chairman of the Spartacist League (US), the original national section of the International Communist League. In his later years, Robertson was consultative member of the ICL's international executive committee.
Trotskyism in Vietnam was represented by those who, in left opposition to the Indochinese Communist Party (ICP) of Nguyen Ai Quoc, identified with the call by Leon Trotsky to re-found "vanguard parties of proletariat" on principles of "proletarian internationalism" and of "permanent revolution". Active in the 1930s in organising the Saigon waterfront, industry and transport, Trotskyists presented a significant challenge to the Moscow-aligned party in Cochinchina. Following the September 1945 Saigon uprising against the restoration of French colonial rule, Vietnamese Trotskyists were systematically hunted down and eliminated by both the French Sûreté and the Communist-front Viet Minh.
The Revolutionary Workers League is a small Trotskyist group formed in the United States in the late 1970s. The RWL still has about 20 active members.
The Spartacist League/U.S. is a Trotskyist political grouping which is the United States section of the International Communist League, formerly the International Spartacist Tendency. This Spartacist League named themselves after the original Spartacus League of Weimar Republic in Germany, but has no formal descent from it. The League self-identifies as a "revolutionary communist" organization.
The International Socialist Group (ISG) was a Trotskyist organisation in Britain. It was the British section of the Fourth International (FI) until 2009 when it dissolved into Socialist Resistance.
The International Committee of the Fourth International (ICFI) is a public faction of the Fourth International founded in 1953. Today two Trotskyist internationals claim to be the continuations of the ICFI; one with sections named Socialist Equality Party which publishes the World Socialist Web Site, and another linked to the Workers Revolutionary Party in the UK.
The International Marxist Group (IMG) was a Trotskyist group in Britain between 1968 and 1982. It was the British Section of the Fourth International. It had around 1,000 members and supporters in the late 1970s. In 1980, it had 682 members; by 1982, when it changed its name to the Socialist League, membership had fallen to 534.
The International Communist League (Fourth Internationalist) abbreviated as ICL(FI), earlier known as the international Spartacist tendency (iSt) is a Trotskyist international. Its largest constituent party is the Spartacist League (US). There are smaller sections of the ICL (FI) in Mexico, Canada, France, Germany, Ireland, Italy, Japan, South Africa, Australia, Greece and the United Kingdom.
The phrase Fifth International refers to the efforts made by groups of socialists and communists to create a new workers' international.
Orthodox Trotskyism is a branch of Trotskyism which aims to adhere more closely to the philosophy, methods and positions of Leon Trotsky and the early Fourth International, Vladimir Lenin and Karl Marx than other avowed Trotskyists.
Anticapitalistas, known as Izquierda Anticapitalista until January 2015 and as Espacio Alternativo from 1995 to November 2008, is a socialist political organisation that works as a confederation in Spain. Anticapitalistas is defined as a revolutionary socialism, anti-capitalist, proletarian internationalist, republican, and eco-socialist organisation, assuming Marxism in an open, plural, and critical sense. Its stated objective is the rebuilding of the revolutionary project through the creation of a unitary, anti-capitalist political expression sustained by the anti-globalisation movement, the labor movement, and the social movements at large. It is a member of the Fourth International (post-reunification), a Trotskyist international organisation reformed in 1963.
Far-left politics in the United Kingdom have existed since at least the 1840s, with the formation of various organisations following ideologies such as Marxism, revolutionary socialism, communism, anarchism and syndicalism.
The International Bolshevik Tendency is an international Trotskyist organisation.