2nd World Congress of the Comintern

The 2nd World Congress of the Comintern was a gathering of approximately 220 voting and non-voting representatives of Communist and revolutionary socialist political parties from around the world, held in Petrograd and Moscow from July 19 to August 7, 1920. The 2nd Congress is best remembered for formulating and implementing the 21 Conditions for membership in the Communist International.

The 2nd World Congress of the Communist International, held in the summer of 1920, has been regarded by scholars as "the first authentic international meeting of the new organization's members and supporters," owing to the ad hoc nature of the 1919 Founding Convention. The gathering is also significant for the level of participation of Soviet leader V.I. Lenin, who participated in the affairs of the gathering more intensely than at any other, preparing a host of key documents and actively helping to chart the gathering's course.

The 2nd World Congress took place at a time of heated world political passion, as British historian E.H. Carr later recalled:

"The second congress marked the crowning moment in the history of the Comintern as an international force, the moment when the Russian revolution seemed most certainly on the point of transforming itself into a European revolution, with the destinies of the RSFSR merged in those of some broader European unit."

Whereas in 1919 no mass Socialist party had participated in the activities of the Founding Convention, the 1920 gathering saw the inclusion of credentialed delegates from several large European groups, including the Independent Social Democratic Party of Germany (USPD), the French Section of the Workers' International (SFIO), and the Social Democratic Party of Czechoslovakia. The Bolsheviks denied permission to attend to the recently formed (January 1920) Ukrainian Communist Party (CPU).

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