Conversation so far:
On what movie did Dimitri Tiomkin work with Frank Capra?
first break from Columbia director Frank Capra, who picked him to write and perform the score for Lost Horizon (1937).
Did he work on subsequent Capra films?
including the comedy You Can't Take It With You (1938), Mr.
Smith Goes to Washington (1939), Meet John Doe (1941), and It's a Wonderful Life (1946).
Did he write the scores for those movies?
He worked on other Capra films during the following decade.
Was It's a Wonderful Life the last movie he did with Capra?
and It's a Wonderful Life (1946).
Did he win any awards for the movies he did with Capra?
CANNOTANSWER.
Was there anything unusual about the scores he wrote for Capra's films?
credited Capra for broadening his musical horizons by shifting them away from a purely Eurocentric and romantic style to a more American style.

Question: Was he involved in the Why We Fight series?
Self-contained rewrite: Was Dimitri Tiomkin  involved in the Why We Fight series?