The occasion for and basis of the historical-critical edition of the works of Duke Anton Ulrich zu Braunschweig und Lüneburg (1633-1714), who was not only a politically and culturally ambitious prince but also an important representative of German Baroque literature, is the extensive manuscript estate in the Herzog August Library and the Lower Saxony State Archive in Wolfenbüttel. It allows - a rare exception for authors of this time - insights into the textual history of the works, which was lengthy and complicated, especially in the case of the extensive novel "Die römische Octavia". Already published are the "Bühnendichtungen" (in 4 partial volumes) and the text part and apparatus of the first and third as well as a first partial volume of the sixth volume of the "Octavia" (in a total of thirteen partial volumes). Further editing work concentrates on the remaining parts of the "Octavia" (Vol. II and IV-VIII as well as supplementary volume with preliminary work).