Alwin was born in Koenigsberg, Germany, (now Kalinigrad, Russia) and studied music, philosophy and literature at the University of Berlin. He was part of the Berliner Hofoper (1910), Assistant Director of the Bayrueth Orchestra (1912), and served in different orchestras at Halle, Posen, Dusseldorf and Hamburg, between 1914-1920.
For eighteen years (1920-1938) Carl Alwin was conductor at the Staatsoper of Vienna, until his dismissal by the new Nazi regime. He went in exile to the USA where he conducted at the Chicago Civic Opera (1939-1940). He then moved to Mexico where he was music instructor at the conservatorium of Mexico City and conducter at Opera Nacional de Mexico (1941-1945). Carl Alwin was married to the opera singer Elisabeth Schumann.