 Sanford was born in Woodbury, Connecticut into a family with deep New England roots.He was the son of Nancy Bateman Shelton (1800–1880) and Nehemiah Curtis Sanford, who made his fortune manufacturing brass tacks and served in the Connecticut Senate for the 16th District.He was a descendant of Governor Thomas Welles, who arrived in 1635 and was the only man in Connecticut's history to hold all four top offices