Furth was born in Chicago, Illinois, the son of George and Evelyn (née Tuerk) Schweinfurth. He was of German and Irish ancestry, and was raised as a Christian Scientist. He received a bachelor of science in speech at Northwestern University in 1954 and received his master's degree from Columbia University.
A life member of the Actors Studio, Furth made his Broadway debut as an actor in the 1961 play A Cook for Mr. General, followed by the musical Hot Spot two years later. He was also known for his collaborations with Stephen Sondheim: the highly successful Company, the ill-fated Merrily We ... read more