[2] After graduating in 1923 with a B.A., Roman served his acting apprenticeship in theater companies in St. Paul and Chicago, eventually spending five years with the Goodman Theatre.

[2] On January 2, 1933, Bohnen took over a lead part in the Group's hit play, Success Story by John Howard Lawson.

In the plays written by his friend, Clifford Odets, for the Group Theatre, he created the roles of Dr. Barnes in Waiting for Lefty, Schlosser in Awake and Sing!, Gus Michaels in Paradise Lost, Tom Moody in Golden Boy and Mr. Tucker in Night Music.

Some of the other artists who summered there were Elia Kazan, Harry Morgan, John Garfield, Lee J. Cobb, Will Geer, Clifford Odets, Howard Da Silva and Irwin Shaw.

He played the Old Man in Jules Dassin's short film The Tell-Tale Heart (1941) Bohnen was cast as President Harry Truman in The Beginning or the End, an MGM docu-drama about the atomic bomb.

After a private screening in late 1946, Truman let it be known that he disapproved of his portrayal regarding the decision to drop atomic bombs on Japan.

The Actors' Laboratory was accused of Communist leanings, and in February 1948 Bohnen and other members of the group were subpoenaed to appear before a California Senate committee.

[1] In her book on the Group Theater, Real Life Drama, author Wendy Smith wrote that the stress of the Lab's difficulties, and his personal problems as a single parent, contributed to his death.