He is the son of Theodore Wood and Jessica H. (Merrick) Friend. He graduated from Williams College with a B.A. in 1953 and from Yale University with a Ph.D. in 1958. In 1960, he married Elizabeth Pierson, who died in 2003. They had three children, Tad Friend, Pier Friend, and Timmie Friend.  His son is the writer Tad Friend.
He also chairs the review panel for the Harry S. Truman Scholarship Foundation. In 2004 he served Distinguished Visiting Professor of Southeast Asian Studies at the Johns Hopkins University, School of Advanced International Studies.