Since its inception, Surrealism appears strongly committed to practical politics. It was a movement that appeared in the heart of the political tensions of the early twentieth century. Its roots lie in the convulsed years of the First World War and it ends in mid-1940 when the Nazi triumphs in France and the artists go to exile.
During this period, the political positions of Surrealism were progressing: from a deep rejection to exacerbated nationalist spirit that was promoted by the European bourgeoisie during the war, through its ill-fated experience with Stalinism until its encounter with Trotskyism in 1938, when André Breton, with the Russian revolutionary Leon Trotsky and the Mexican muralist Diego Rivera drafted the “Manifesto for an Independent Revolutionary Art.” It is good to know the background of this headway.
On the eve of the start of the First World War, the European bourgeoisie managed to convince people of the need to participate in the war; even the vast majority of the revolutionary parties that belonged to the Second International, infected by the enthusiasm of war, voted for war credits in their respective countries .This led to the massive incorporation of the various militias and thousands of young people would be led to the slaughter, while thousand others would return mutilated from the front. The German artist Georg Grosz, will address this issue in his work.
While this was happening, hundreds of pacifists and defeatists  were assembling in Switzerland, even some artists who expressed their rejection to bourgeois nationalism. They are the same who soon would meet at the Cabaret Voltaire under the name of Dadá  and whose basic assembly point was the strongest condemnation of the war, perceived by them as the throes of a capitalist society in agony. This anti-war, anti-bourgeois and anti-artistic sense of Dadá deeply marked the surrealist spirit.
After the war, a sense of disaster spread throughout the European society, but also of revolutionary temper . Most of the artists who belonged to the Dadá movement join the ranks of Surrealism. This movement was already enjoying organic life since the publication of the French magazine “Litterature” where the political positions of the Surrealist artists can be subtly noted. But it was not until the publication of the first Surrealist Manifesto in 1924 that the Surrealist movement would address the problems facing the relationship between individual freedom and social emancipation. It was this key issue that would govern its relationships as a group between the mid twenties and 1935 and, at the same time, its links with political organizations. An international development would force the Surrealists to establish this partnership.
The trigger factor of this process was the colonial war between France and Morocco. A new nationalist wave in France that would clash with the positions of the Surrealists, speeded up their political definition and ensured their entry to the ranks of the French Communist Party in 1927. This relationship with Stalinism suffers ups and downs, full of tensions. The “marriage” will last until 1932, when Breton and the others break with the Communist Party. The reason was the claims of the Stalinist bureaucracy to exercise a command over intellectual and artistic creation.
What aparted them from Stalinism was precisely what approached them, especially Breton, to Trotskyism. In 1938, the veteran leader of the Russian Revolution, Leon Trotsky wrote an article in which, attacking the “socialist realism” promoted by Stalinism, states: “The art of the Stalinist period will remain as the frankest expression of the profound decline of the proletarian revolution.”  Thus, Trotsky had claimed capital issues for Surrealism: the freedom of art and its independence from the revolutionary leadership. Surrealism finds in Trotskyism the support that would prevent it from compromising with the bourgeoisie. The artists could work out revolution and remain committed to it without being controlled by the party.
When the World War II broke out, the Surrealists were already facing the furious advance of Nazism. When Hitler occupied Paris, most surrealist artists went into exile. At that time, in August 1940, Trotsky was assassinated by the Stalinist ice axe. From the right and the left, the circle was closing around the Surrealist movement. It was the end of a movement that programmatically raised the banner of the desire for freedom and of the unity of man in a new reality, the one of the socialist society.
 With two exceptions: the Russian and Serbian parties voted against.
 Defeatists were those who proposed the defeat of the different national bourgeoisies – and therefore of their own country for the sake of the socialist revolution.
 The founders of the Dadá movement were the Romanian Tristan Tzara, the Germans Hugo Ball, Richard Huelsenbeck, Hans Richter, Hans Arp and his future wife Sophie Tauber.
 The First World War as Lenin had warned was the midwife of revolution. The revolutionary tide ended with Czarism in Russia and spread to Germany, reaching Berlin and other cities.
 Trotsky, Art and politics in our epoch, in www.marxists.org/archive/trotsky/1938/06/artpol.htm