Dr. French was born in Middlesex, New York on January 20, 1822. He was the son of Harvey and Amanda Hazelton French. His father was a veteran of the War of 1812. He attended local schools before moving to Michigan where he attended Albion Seminary. While in Hillsdale County he studied medicine and practiced as a doctor for some years. In 1845 he went to Fort Leavenworth, Kansas where he enlisted in the US Army at the start of the Mexican American War and entered the service as a private even though he was a practicing physician in civilian life.