The International re-formed in 1923 ( as the Labor and Socialist International ) , and was re organised again , in its present form , after World War II . Many social democratic and socialist parties had been suppressed in Nazi-occupied Europe ) . The International re-formed in 1923 ( as the Labor and Socialist International ) , and was reconstituted again , in its present form , after World War II ( during which many social democratic and socialist parties had been suppressed in Nazi-occupied Europe ) .