Fürmann was born in Berlin-Kreuzberg. At the age of 15 he lost both his parents. At 17, he had a serious accident while train surfing, and had to spend six weeks in the hospital as a result. Fürmann left school after his O-levels (roughly 10th grade) and after that worked as a waiter, bouncer, and drifter. In 1991 he went to New York and studied acting at the Lee Strasberg Theatre Institute.