We have the following via "The Twelve Key," the blog of “Claire Kluskens, a Census/Genealogy Subject Matter Expert and Digital Projects Archivist at the National Archives and Records Administration (NARA), Washington, DC”:
Staff members at the National Archives at Chicago are tagging various records series in Record Group 21, Records of District Courts of the United States, to make them more accessible to a wider audience.More. Dan Ernst. H/t: JG
One of these series is the U.S. District Court, Detroit, Repatriation Records, 1918-1970 (National Archives Identifier 1150838). Between 1907 and 1922, women lost their U.S. citizenship if they married a foreign national. Later, many women wished to regain their U.S. citizenship. Depending upon when they applied, the women were required to file either a Petition for Naturalization or take the Oath of Allegiance. This series primarily includes the latter document.