John W. O'Malley, American Catholic historian, academic and Jesuit priest
John William O'Malley (born June 11, 1927) is an American academic, Catholic historian, and Jesuit priest. He is a University Professor at Georgetown University, housed in the Department of Theology and Religious Studies. O'Malley is a widely published expert on the religious history of Early Modern Europe, with specialities on the Council of Trent, the Second Vatican Council, and the First Vatican Council.