Litwack was born in Santa Barbara, California in 1929, and received his B.A. in 1951 and Ph.D. in 1958 from the University of California, Berkeley. He has taught at the Universities of Wisconsin and South Carolina and at Colorado College.

Litwack's interest in history was sparked by The Growth of the American Republic, by Samuel Eliot Morison and Henry Steele Commager.Litwack said, "The textbook was my first confrontation with history. I asked my 11th grade teacher for the opportunity to respond to the textbook’s version of Reconstruction, to what I thought were distortions and racial biases. (I had already read Howard Fast’s Freedom Road.) The research led me to the library...and to W. E. B. Du Bois’s Black Reconstruction, with that intriguing subtitle: An Essay Toward a History of the Part which Black Folk Played in the Attempt to Reconstruct Democracy in America, 1860—1880. Armed with that book, I presented what I thought to be a persuasive rebuttal of the textbook." Interview with Leon F. Litwack

Historian Michael Les Benedict wrote that, in 1961, "Leon Litwack showed how the federal government's pervasive support for slavery led to shameful treatment of free African Americans." Benedict was referring to pages 30—63 of chapter 2, titled "The Federal Government and the Free Negro" in Litwack's book, North of Slavery: The Negro in the Free States, 1790-1860.

From 1964 to 2007, Litwack taught at the University of California in Berkeley, where he instructed more than 30,000 students. For much of that time, he taught the introductory course in post-Civil War American History, and was the Alexander F. and May T. Morrison Professor of American History. Litwack gave his final lecture as a professor, "Fight the Power," on Monday, May 7, 2007 in Wheeler Auditorium.

He was elected to the presidency of the Organization of American Historians. An enormously popular and influential teacher, Litwack was profiled in Newsweek's 2006 edition of the "Giving Back Awards," having been nominated by one of his former students. Reader's Choice | Newsweek.com He has received two distinguished teaching awards. Litwack was presented with the Golden Apple Award for Outstanding Teaching in 2007 by the ASUC at the University of California, Berkeley.

With a National Endowment for the Humanities Film Grant, he produced To Look for America in 1971. Litwack followed up his groundbreaking book on Reconstruction, Been in the Storm So Long, with Trouble in Mind, which continued his investigation of race relations into the early-20th Century. Litwack's sequel to Trouble in Mind is titled How Free Is Free?: The Long Death of Jim Crow (The Nathan I. Huggins Lectures) and focuses on black southerners and race relations from the 1930s to 1955.

A distinguished lecturer with the Organization of American Historians, Litwack lectures on these topics:

• Pearl Harbor Blues: Black Americans and World War II
• Trouble in Mind: African Americans and Race Reflections from Reconstruction to the Civil Rights Movement
• On Becoming a Historian
• To Look for America: From Hiroshima to Woodstock (an impressionistic multi-media examination of American society, with an introductory lecture on American society after 1945)
• Fight the Power: Black Americans and Race Relations after the Civil Rights Movement

"So what else is there to say but that everything has changed and nothing has changed. And Fight the Power. And 'Go Bears!' "- May 7, 2007 to close his final lecture.