Deloit was the first community in Crawford County in western Iowa to receive postal service, when it was established at the location in 1855. The community was originally referred to as Mason’s Grove, before undergoing a series of name changes, to Boyer Valley, then Bloomington, and then Beloit, after the city in the neighboring state of Wisconsin. To avoid any potential confusion, the “B” was replaced with a “D,” and the name “Deloit” was officially adopted in January 1872.