This thesis argues for a coherent theory of the animal in the written and visual works of the German Expressionist painter, Franz Marc. By contextualizing Marc’s animal theory within the history of animal studies, this thesis will analyze how Marc’s animal theory corresponds with several central concepts within this field. One of these concepts—a theory of animal death—is central to the artist’s greater theory of the animal and to the analysis this thesis provides. In examining Marc’s theory of animal death, the following work will propose that the artist’s theory of animal spirituality is his greatest legacy within the field of animal theory.