The Oneida Community Mansion House in Oneida, New York, was the center of the Oneida Community, a religious communal society led by John Humphrey Noyes that moved there from Vermont in 1848. Built and expanded over several decades, it was designed to support shared living through common meals, gathering spaces, rotating rooms, and the community’s social practices. Later additions reflected changes including the childbearing program called stirpiculture and a population nearing 300. After the communal experiment ended in 1880, the society became Oneida Community, Ltd. The complex remained continuously occupied and survives as a rare, important site of 19th-century American utopianism.