William Markus, born Karl William Marcus, was a Finnish-British film director, actor, screenwriter, and producer. Born in Liverpool to a Finnish father and an English mother, he held dual citizenship in Finland and the United Kingdom. Markus began his acting career in 1944 and later transitioned into directing. He directed 13 films between 1953 and 1965, with notable works including Miriam (1957), which was entered into the 8th Berlin International Film Festival. His films often explored complex social themes, contributing significantly to Finnish cinema during his active years.