Irwin Unger (born 1927, Brooklyn, New York) is an American historian and academic specializing in economic history, the history of the 1960s, and the history of the Gilded Age. He earned his Ph.D. from Columbia University in 1958 and is currently Professor Emeritus of History at New York University.
Unger won the Pulitzer Prize for History in 1965 for his book, The Greenback Era.
Among Unger's published books are:
- The Guggenheims: A Family History, (with Debi Unger, 2005)
- LBJ : A Life, (with Debi Unger, 1999)
- The Times Were a Changin': The Sixties Reader (with Debi Unger, 1998)
- The Best of Intentions: The Great Society Programs of Kennedy, Johnson and Nixon (1996)
- Turning Point, 1968, (with Debi Unger, 1988)
- These United States: The Questions of Our Past (1978)
- The Vulnerable Years: The United States, 1896-1917 (1977)
- The Movement: The American New Left 1959-1973 (1973)
- The Greenback Era (1965)
In addition, Unger has written a number of textbooks on modern American history.