The International Workingmen's Association, sometimes called the First International, was an international organization which aimed at uniting a variety of different left-wing political groups and trade union organizations which were based on the working class. It was founded in 1864 in a workmen meeting held in Saint Martin's Hall, London. Its first congress was held in 1866 in Geneva.

Originally, the organization contained British trade unionists, anarchists, French socialists and Italian republicans, and it was led by Karl Marx. Some time later, disputes between Marx and Mikhail Bakunin, the most prominent anarchist in the International, led to a split between the Marxists and the Anarchists, in which Bakunin's followers were ejected from the International. In 1872, the organization was relocated to New York City. The First International disbanded 4 years later, at the 1876 Philadelphia conference. Attempts to revive the organization over the next five years failed. However, the Second International was established in 1889 as its successor.

The First International was largely considered to be a major factor leading to the creation of the Paris Commune of 1871. Although this idea is disputed, Marx did write a defense of the Commune.

See also

• Second International and Socialist International
• Third International (Comintern)
• Fourth International and Trotskyist internationals

• The Internationale