Conversation so far:
What branch of military did the American football coach Bill Edwards serve in?
American football coach Bill Edwards enlisted in the U.S. Navy later in 1942 as America's involvement in the war intensified.
What is the Western Reserve in relation to American football coach Bill Edwards?
American football coach Bill Edwards left to coach the freshman football team at Western Reserve University in Cleveland, Ohio in 1933.
What year did American football coach Bill Edwards graduate?
When did American football coach Bill Edwards begin coaching?
American football coach Bill Edwards got his first coaching job in 1931, when he was hired as an assistant football coach at Springfield High School.
What team did American football coach Bill Edwards first coach for?
After visiting with Detroit Lions owner Fred Mandel, American football coach Bill Edwards ultimately was hired in February 1941.

Question: How long did he coach for the Lions?
Self-contained rewrite: How long did American football coach Bill Edwards coach for the Detroit Lions?