Nikolaus von Amsdorff, one of Luther’s closest friends and the first protestant bishop ever, engaged himself intensely in the preservation of the protestant heritage during the controversies following the Augsburg Interim of 1548. Loyally he adhered to John Frederick the magnanimous, even during the duke’s imprisonment and although he lost an important part of his dominion to his cousin Moritz. Amsdorff, meanwhile expelled from his bishopric, joined the theologians at Magdeburg, who called for resistance against the Augsburg and the Leipzig Interim. The edition of 16 texts written by Amsdorff in the years between 1546 and 1558 elucidates his position. The volume provides the reader with a concise description of Amsdorff’s whole life. Reichert’s standard work is now printed for the first time, augmented with some bibliographical notes and three indices.