This is a comprehensive study of the influence of Swabian Pietism on the early life and works of Friedrich Schiller. Besides integrating earlier research on the subject, the author has also sought out those documents of Pietism in Wuerttemberg which were widely known and/or were in the possession of the Schiller family. Through a comparison with Schiller’s own words striking similarities, if not always direct influences, are demonstrated. This is also the first study to explore the possible connections between Schiller’s thought and the ideas of Friedrich Christoph Oetinger. Evidence is also presented that, in spite of Kant’s later influence on Schiller, his mature philosophy is firmly rooted in the theology of Swabian Pietism.