Cooper married Lorraine Rowan Shevlin on March 17, 1955, in Pasadena, California, just ten days before leaving for India. Twice divorced, Shevlin was the daughter of Robert A. Rowan (a wealthy California real estate developer whose projects included the Hotel Alexandria and the Security Building), step-daughter of Vatican official Prince Domenico Orsini, and a well-known socialite. She was fluent in three languages and understood Russian. The two had dated for much of the 1950s, but Cooper was hesitant to marry because he had doubts about moving into Shevlin's elaborate Georgetown home. (While in Washington, the unmarried Cooper permanently resided in the Dodge House Hotel.) The move to India removed this barrier, and Secretary of State Dulles encouraged Cooper to marry her before leaving so that the U.S. embassy in New Delhi might have a proper hostess. On April 4, 1955, the couple stopped in England on their way to India to visit with Louis Mountbatten, the last Governor-General of India prior to India's achieving its independence. Their discussions about the situation of the Indian people were part of the scant preparation Cooper received before arriving there.