Communist support grew from 10% in 1928 to 15% by 1932, an extra million voters making it the largest Communist Party in the world outside the Soviet Union.
Most of their support came from the working classes who wanted to defend their jobs and wages against big business.
However, this growth also helped the Nazis as they were increasingly seen as the only defence against Communism by a frightened middle and upper class who feared their status and wealth would disappear under a Communist government.
