David Gaub McCullough (July 7, 1933 – August 7, 2022) was an American popular historian. He was a two-time winner of both the Pulitzer Prize and the National Book Award. In 2006, he was given the Presidential Medal of Freedom, the United States' highest civilian award.

Born and raised in Pittsburgh, McCullough earned a degree in English literature from Yale University. His first book was The Johnstown Flood (1968), and he wrote nine more on such topics as Harry S. Truman, John Adams, Theodore Roosevelt, the Brooklyn Bridge, the Panama Canal, and the Wright brothers. McCullough also narrated numerous documentaries, such as The Civil War by Ken Burns, as well as the 2003 film Seabiscuit, and he hosted the PBS television documentary series American Experience for twelve years. McCullough's two Pulitzer Prize–winning books—Truman and John Adams.—were adapted by HBO into a TV film and a miniseries, respectively.