Isaac Demund was born in Ovid, Seneca County, NY in 1837. He was a son of Quam Demund and his first wife Lydia Demund, and the brother of Clara Demund Webb of Caroline. He married Lydia Martha (Stout?), born in 1839.

Research about the Demund family appears in: Judith Wellman, Tanya Warren, Historical New York Research Associates "Discovering the Underground Railroad, Abolitionism, and African America Life in Seneca County, New York, 1820-1880," sponsored by the Seneca County Historian's Office, 2006, 41-47, and as Tanya L. Warren, "The Demund Family of Ovid and Lodi," also in this publication, no page numbers, available on the Seneca County Historian's Website: https://www.senecacountyny.gov/gov/admin/historian/