Just finished second part of the K.H.Wiik's biography (Tuomioja 1979 & 1982). Wiik being one of the most upfront marxist social-democrats of the first half of 20th century, the biography gives a nice view of the Finnish social-democrat movement as whole.
Wiik was against the Finnish revolution of 1918 but unlike most of the socialists who didn't exile to Russia, Wiik never gave up his marxism, yet he kept a strict line towards the communists. He was kicked from the party during the Intermin Peace (1940-1941) and imprisoned after the operation Barbarossa was launched.
After the war, Wiik turned into new left-democratic alliance but disillusioned shortly after, just before death at the age of 62.