The Puerto Rico Citizenship Archives Project (PRCAP) is part of a public repository designed to document the legal history of the extension of citizenship to the U.S. territories. The PRCAP provides a comprehensive overview of 120+ year story of debates over the extension of citizenship to Puerto Rico. It also provides public access to the key historical documents shaping this history. The main goal is to create a reliable public archive of primary documents that can foster new research projects on Puerto Rico and its relationship to the United States as well as on broader visions of U.S. citizenship.