Conversation so far:
Where did David M. Shoup receive his early education?
David M. Shoup was enrolled in Covington High School, a competitive high school with an advanced curriculum and maintained high marks in French, English, physics, and history.
What did David M. Shoup do after Covington High School?
After high school, David M. Shoup attended DePauw University, where he was one of 100 awarded the Edward Rector Scholarship, giving him full tuition.

Question: When did he join the Military?
Self-contained rewrite: When did David M. Shoup join the military?