This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
The Society of Saint Vincent de Paul was founded on 23 April 1833 in Paris, not by clergy but by a group of laypeople led by Frederic Ozanam, then a young university student, and Emmanuel Bailly, organized around the specific practice of person-to-person service of the poor, direct home visits rather than institutional charity administered at a distance. That lay, home-visiting model was deliberately portable, and it reached the United States within Ozanam's own lifetime: the United States Society was established on 20 November 1845 in St. Louis, Missouri, barely twelve years after the Paris founding.
The National Council of the United States Society of St. Vincent de Paul, the American Society's coordinating body, is now headquartered in Maryland Heights, Missouri, and stands over a structure that has grown to roughly 4,000 local Conferences and Councils spread across the country. The organization's basic unit was never the national office; it was, and remains, the Conference, a small local group of lay volunteers called Vincentians who make direct home visits to people in need, a model of service essentially unchanged in its method from the one Ozanam and Bailly began with two laypeople and a handful of companions in Paris.