Richard Ullman, the David. E. Bruce Professor of International Affairs, Emeritus, at Princeton University, died of Parkinson's disease March 11 at Park Place Center in Monmouth Junction, N.J. He was 80.

Former colleagues and students of the Woodrow Wilson School of Public and International Affairs remembered Ullman, who was on the Princeton faculty from 1965 until 2001 and became an emeritus professor in 2002, for his influence as a progressive commentator on U.S. foreign policy and world affairs. He was also known for his mentorship of generations of students and as a prolific scholar in the field of international security.

After he received his doctorate from the University of Oxford, where he had studied as a Rhodes Scholar, Ullman's thesis on British-Soviet relations from 1917 to 1921 was published as a trilogy, launching his academic career. His work caught the eye of George Kennan, an American adviser and diplomat and a key figure in the emergence of the Cold War who mentored Ullman at Oxford.

Throughout his career, Ullman published hundreds of academic papers on foreign policy and became well known for helping to broaden the scope and concept of security. Ullman was among those who helped to compile the Pentagon Papers and served in many governmental and academic positions....