The edition makes accessible for the first time the complete correspondence between the collector and founder of the Folkwang Museum Karl Ernst Osthaus and the painters Henri Matisse and Hans Purrmann. The correspondence thus opens up new sources on the early reception history of Matisse's works in Germany, on the genesis of early major works by the painter, and on the founding of the Académie Matisse. The edition of the widely scattered correspondence offers numerous new insights not only for Matisse research, but also for the study of Hans Purrmann and the founder of the Folkwang Museum. The correspondence is supplemented by a foreword from the Hans Purrmann Archive as well as an introduction by the editors, an index of persons, and a bibliography. The scientific study of the correspondence offers a variety of new insights into Matisse, Osthaus, and Purrmann. Numerous previously unpublished letters The volume continues the series of the Purrmann Edition Look Inside