Origen (c. 184–253 AD) was one of the most prolific and influential theologians of early Christianity. Born in Alexandria, Egypt, he studied under the philosopher Clement of Alexandria and became head of the renowned Alexandrian Catechetical School. A deeply devoted scholar, Origen produced an extraordinary body of work, including "Hexapla", a monumental comparative edition of the Old Testament, and "De Principiis" ("On First Principles"), considered the first systematic Christian theology. His allegorical approach to Scripture and synthesis of Christian thought with Greek philosophy shaped theological discourse for centuries, even as some of his ideas later sparked considerable controversy.