Nicholas of Cusa (Cusanus, 1401-1464) was a provocative thinker - particularly if read as the mediator of conflicts: He harmonized religion and politics, faith and philosophy, and the theologies of his time. This book outlines his place within Renaissance humanism, his philosophy of religion, his mysticism and his philosophical theology. Cusanus' contribution to religious peace and harmony plays an exemplary role in this study. In this Renaissance thinker and Cardinal we find seeds of modern approaches to toleration - including its inherent paradoxes. Cusanus' terminology was neither scholastic nor classicist, and therein he set standards for content driven philosophical language. This becomes clear in comparisons with the idiosyncratic late medieval philosopher Raymond Lull and with a 17th-century translation of his On the Vision of God.