Conversation so far:
What were some political activities that Robert Dale Owen partook in?
During the American Civil War, Robert Dale Owen served in the Ordnance Commission to supply the Union army; on March 16, 1863, he was appointed to the Freedman's Inquiry Commission.
What did the Ordnance Commission supply the union with?
The broad mission of the Ordnance Corps is to supply Army combat units with weapons and ammunition, including at times their procurement and maintenance.

Question: What were these letter include?
Self-contained rewrite: What did the letters written by Robert Dale Owen include?