He was educated at The Hill School,[1] then majored in history at Princeton University, graduating in 1974.

[3] Prior to his career as a journalist and historian, Gwynne was a French teacher at Gilman School in Baltimore, Maryland.

He was an international banker with both Ameritrust in Cleveland, Ohio and First Interstate Bank in Los Angeles and traveled extensively overseas.

[8] His book Rebel Yell, a biography of Stonewall Jackson – also a New York Times Bestseller – was a finalist for the PEN Award for Literary Biography and for the National Book Critics Circle Award in history.

His newest book, His Majesty's Airship: The Life and Tragic Death of the World's Largest Flying Machine, was released on May 2, 2023.