Born in Baltimore and raised in Cedarcroft, he was the grandson of George Henry Van Hollen, a seafood packer and owner of the Atlantic Packing Co. The family also developed the Cedarcroft section of North Baltimore and lent its name to Hollen Road. His father, Donald Van Hollen, was a Baltimore Gas and Electric Co. employee who later worked at the family's seafood business. His mother, Cecilia Harvey Coale, was a former League of Women Voters secretary.
Dr. Van Hollen was a 1941 graduate of Gilman School, where he played lacrosse and football. His son, U.S. Rep. Christopher Van Hollen, said his grandparents were ardent supporters of Franklin Roosevelt and his father enjoyed political debates as an adolescent.
"He often jubilantly recalled that when Roosevelt was running for a second term in 1936 against former Republican Gov. Al Landon, the vast majority of his classmates, whose parents viewed Roosevelt as a 'traitor to his class,' sported Landon buttons while he and a beleaguered few bravely wore their FDR buttons — and won," said his son, who lives in Kensington.
According to an autobiographical sketch that Dr. Van Hollen wrote, he began studies at Haverford College in suburban Philadelphia. He enlisted in the Navy in 1942 and served until the war ended. He left military service as a lieutenant aboard a high-speed transport ship.
After the war, he returned to Haverford and earned a bachelor's degree and then attended the Johns Hopkins University, where he received a doctorate in political science. He also studied at the University of California, Berkeley and was a graduate of the Naval War College.
"While at Johns Hopkins, he managed the 1948 Democratic primary campaign for congressional candidate Leo McCormick, the former director of the Maryland Office of Price Administration during World War II, against incumbent Congressman George Fallon," his son said. "My father's candidate was easily defeated but he often joked that it prepared him to do much better 54 years later when he went door-to-door to help elect me to Congress."
After leaving Hopkins in 1951, he joined the executive secretariat for Dean Acheson, then secretary of state. He covered the Conference on Indo-China in Geneva and attended the February 1952 NATO Ministerial meeting in Lisbon, where both Portugal and Greece were admitted into NATO membership, his son said.
The family sketch said that in 1953 Dr. Van Hollen married Edith Eliza Farnsworth, who had been working as a Russian studies expert at the Central Intelligence Agency. She was later the chief analyst for Afghanistan in the Bureau of Intelligence and Research at the State Department and was later South Asia division chief.
In 1955, he became a political officer in New Delhi and subsequently served in Calcutta, Pakistan and Turkey.
In 1969, he was appointed deputy assistant secretary for the Near East and South Asia, where he "butted heads" with National Security Adviser Henry Kissinger over the handling of the Bangladesh crisis in 1971, his son said.
President Richard M. Nixon nominated him as ambassador to Sri Lanka and the Maldives in 1972.
"He helped strengthen U.S.-Sri Lankan relations during a critical period when the United States and the Soviet Union were competing for influence in Sri Lanka and the Indian Ocean," his son said. "He was an amateur but avid genealogist. He also helped promote U.S.-Sri Lankan relations in a very personal way by discovering a family link with Sri Lanka through an ancestor who had served as an American missionary to the island in the early 19th century."
Mr. Van Hollen liked the outdoors and camping. He spent time at a family home in Vermont. The Green Mountain Club awarded him an End to Ender badge for hiking from Massachusetts to Canada. He also wrote a history of Vermont's Big Basin Forest.
In addition to his son, survivors include two daughters, Caroline Van Hollen of Washington, D.C., and Cecilia Van Hollen of Fayetteville, N.Y.; two sisters, Margaret Lee of Baltimore and Cecilia Van Hollen Ives of Peterborough, N.H.; and five grandchildren. His wife of 54 years died in 2007.
Plans for a funeral service are incomplete.