The Bordesholm Altar in the Schleswig Cathedral is one of the most famous carved altars of the Middle Ages due to its size and exceptional quality. It is all the more surprising that there has been little interest from previous research in its creator, Hans Brüggemann. This monograph publishes the preserved complete work for the first time in the form of a scientific catalog. The historical context connects the work to the significant political changes that Schleswig-Holstein faced shortly before the introduction of the Reformation. Brüggemann was more than just an outstanding artist; his distinctive style can also be understood as an expression of the political stance of his patrons. In clear distinction from Denmark and Lübeck, a artist was brought into the region who was able to give a completely independent character to the representative foundations of the high nobility.