ドイツ社会主義労働者党
Ledebour remained in the USPD after the splits in that party in 1920–22, when most of the membership merged with the Communist Party of Germany (KPD) in 1920, and most of the rest merged with the SPD in 1922. In 1931 he joined the Socialist Workers' Party of Germany (SAPD). He went into exile in Switzerland after Adolf Hitler became Chancellor of Germany in 1933, and died in Bern in 1947 after a long illness.