Complex sentence: Lewis P. Firey (11 April 1825--5 March 1885) was a Southern Unionist who served in the Maryland State Convention, and, during the American Civil War, the Maryland State Senate; he was the originator of the project for the Antietam National Cemetery.
Split into simpler sentences: Lewis P. Firey (11 April 1825--5 March 1885) was a Southern Unionist who served in the Maryland State Convention, and the Maryland State Senate during the American Civil War. He was the originator of the project for the Antietam National Cemetery.