When the Sea Came Alive: An Oral History of D-Day is a New York Times bestselling book by Pulitzer Prize finalist and historian Garrett M. Graff, published by Avid Reader Press/Simon & Schuster in June 2025. The book tells the story of June 6, 1944—the largest seaborne invasion in history—through more than 700 firsthand eyewitness accounts drawn from soldiers, nurses, pilots, sailors, children, politicians, photographers, and journalists who participated in or witnessed the Allied landing on the beaches of occupied northern France.

Graff weaves together these voices to create a ground-level portrait of D-Day, capturing the chaos, heroism, fear, and sacrifice of a single day that changed the course of World War II. The book highlights underrepresented perspectives, including Black soldiers who landed on the beaches and women such as war correspondent Martha Gellhorn. Available in hardcover, paperback, eBook, and audiobook formats.