Walid Ahmad Samih Khalidi (July 16, 1925 – March 8, 2026) was a Palestinian historian educated at Oxford University who wrote extensively on the 1948 exodus of Palestinians. He was a co-founder of the Institute for Palestine Studies, established in Beirut in December 1963 as an independent research center focused on the question of Palestine and the Arab-Israeli conflict, and served as its secretary-general until 2016.

Khalidi’s first teaching position was at Oxford, a post he resigned from in 1956 in protest against the Tripartite Aggression in which Britain participated. He was a professor of political studies at the American University of Beirut until 1982, and subsequently a fellow at the Harvard Center for International Affairs. He also taught at Princeton University.

He was a Fellow of the American Academy of Arts and Sciences. Khalidi had a significant impact on research, institutional development, and diplomacy. His academic work in particular – according to Rashid Khalidi – played a key role in shaping Palestinian and Arab reactions to the occupation of Palestine, and helped define the ways in which Palestine could maintain its place on the map of the Middle East.