Between 1809 and 1810, a project was developed aimed at incorporating into the archives of the Empire in Paris the largest and richest documentary collections from the annexed departments and satellite countries. In 1814, hundreds of thousands of diplomas, registers, and bundles of documents from Italy, Vienna, and Spain were piled up in the palais de Soubise, and more materials were expected from Belgium, Geneva, and Holland. Most of these archives were returned to their respective countries with the Restoration. This article explores the origin of the Napoleonic « Annexation » of the archives of Europe, the political stakes, and themotivations of the protagonists, in particular the Garde des Archives, Pierre-Claude-François Daunou, whose name invites reflections about a continuity with the Republican era. Moreover, this article analyzes the dynamics that developed in the designated territories, especially in two very different instances – Rome and Florence. The centralization of the archives rapidly became of highly complex operation, similar to the very construction of the Empire, because of the diversity of local situations and the roles played by the participants.