Erich Raddatz (28 November 1886 – 16 February 1964) was a Berlin city politician and parliamentarian. He was a founder member of the Communist Party, but was among those excluded from it in 1931 after openly opposing the leadership's adoption of Stalin's "social fascism" doctrine. After the war he returned to the Social Democratic Party with which he had broken over its support for the war back in 1917. He remained active in city politics well into his 70s, by which time he had become known to Berliners as "Papa Raddatz".