This book focusses on Nietzsche's Der Antichrist as the first part of Nietzsche's planned four volume work (which was never completed) and explores how situating it in this way affects our understanding of Der Antichrist and The Revaluation of All Values, as well as of Nietzsche's late philosophy more generally. The book considers what Der Antichrist can reveal about the four volume project and its philosophical project of the revaluation of values. It examines Nietzsche's other late books, his notebooks, and his letters in order to better understand the planned four volume work and the philosophical meaning of the revaluation of all values. Nietzsche thought deeply about values and this study of his late views (1883-1888) provides insights into value systems more generally. Nietzsche's 'The Antichrist' as Part of and Key to His Unfinished 'Revaluation of All Values' is essential reading for all scholars, researchers and advanced students of Friedrich Nietzsche. Thomas H. Brobjer is a professor in the Department of the History of Ideas and Science at Uppsala University, Sweden. He has written several books on Nietzsche, among others: Nietzsche's Ethics of Character (1995), Nietzsche and the 'English' (2008), Nietzsche's Philosophical Context (2008), Nietzsche's 'Ecce Homo' and the Revaluation of All Values (2021), Nietzsche's Knowledge and Reading of Philosophy (2023), 'Twilight of the Idols' and Nietzsche's Late Philosophy (2023), and The Close Relationship between Nietzsche's Two Most Important Books (2023).