The Virgin Mary provided a powerful focal point for religious identity. During the early modern period Mary-worship marked out one Christian confession from another, rather than Christian from Jew, as in the Middle Ages, or Catholic from secularist, as in more modern times. Intra-Christian disputes over Mary’s status were particularly intense in Germany, the heartland of the Reformation, where Catholic and Protestant lived side by side. This paper will consider the fate of Marian imagery and devotion in three of Germany’s key free cities: Nuremberg, Augsburg, and Cologne. Each city had a different confessional structure: Nuremberg adopted the Lutheran faith in 1525; Augsburg’s council introduced wide-ranging and radical (Zwinglian-influenced) reforms in the 1530s but the city had religious parity imposed on it in 1548; Cologne remained Catholic, despite the presence of a considerable Protestant minority within its city walls and the attempts of two archbishops to introduce a synodal Reformation. These three cities therefore illustrate the spectrum of possible responses of traditional Marian veneration to the pressures of Protestant and Catholic reform. A comparison between them allows us to assess the impact of both doctrinal debate and local circumstance on the expression of Marian piety, and reveals the various ways in which Marian devotion might be used to create confessional consciousness and define religious allegiance.