Johnson was born in Cleveland, Ohio. He was descended from the Jansen family of New Amsterdam, and included among his ancestors the Huguenot Jacques Cortelyou, who laid out the first town plan of New Amsterdam for Peter Stuyvesant. He attended the Hackley School, in Tarrytown, New York, and then studied at Harvard University as an undergraduate, where he focused on history and philosophy, particularly the work of the Pre-Socratic philosophers. Johnson interrupted his education with several extended trips to Europe.[9] These trips became the pivotal moment of his education; he visited Chartres, the Parthenon, and many other ancient monuments, becoming increasingly fascinated with architecture.