parker was born in keene, new hampshire on may 5, 1847. he was educated locally and joined the union army for the american civil war. he served as a private in the 2nd new hampshire infantry, 14th new hampshire infantry, and 6th regiment of the veteran reserve corps. he later received a second lieutenant's commission in the 6th u.s. volunteer infantry, and he ended the war as a brevet first lieutenant.