Conversation so far:
How did Burt Bacharach begin work as an musician?
Following his tour of duty in the United States Army, Bacharach spent the next three years as a pianist.
What else was he known for?
He then became part-time music director for Dietrich, the German actress and singer.

Question: What year was that?
Self-contained rewrite: What year did Burt Bacharach become part time music director for Dietrich?