Isaac Mann was born in Virginia on March 24, 1791. He served as a Private in Captain John Williams Company of the Ohio Militia during the War of 1812. This company was the first to be stationed at Fort Loramie during the War of 1812.
In 1813, he married Abigail "Catherine" Williams, daughter of John and Elizabeth Tawney Williams. Family tradition states that he was well educated, having attended college until the age of twenty-one. Isaac owned and operated the first sawmill in Shelby County. The sawmill was located in Ft. Loramie, Ohio.
Isaac and his family lived in Oran, Ohio. The present day crossroads in this village are located near the center of his farm.