Abstract The Bibliothèque wallonne accommodates a church collection that is the result of distinct archival policies. Tracing the archival history of this collection reveals important shifts in its formation, accessibility, and usage. A travelling archive from 1578, it became a fixed church archive in 1777, and in 1852 was augmented by a separate Walloon Library, with both archives under the management of a Commission des Archives. In 1877, the Commission de l’ histoire des Églises wallonnes was established, whose goal was to write the history of the Walloon churches in the Netherlands, and collecting the necessary sources for doing so. In 1893, after the activities of both commissions were merged, the collections were combined to form what is now the Bibliothèque wallonne. Established primarily as a church archive, the collection is now mostly used for researching the history of the Walloon churches in the Netherlands.