The Steel Strike of 1919 was an attempt by the weakened Amalgamated Association of Iron, Steel and Tin Workers (AA) to organize the United States steel industry in the wake of World War I. The strike began on September 22, 1919, and collapsed on January 8, 1920.The AA had formed in 1876. It was a union of skilled steel and ironworkers which was deeply committed to craft unionism. However, technological advances had slashed the number of skilled workers in both industries.