It is not often that an historian joins the ranks of authors on the bestseller lists, but Stephen E. Ambrose has managed to do just that with a clutch of historical accounts of World War II--including D-Day, June 6, 1944: The Climactic Battle of World War II and its sequel, Citizen Soldiers: The U.S. Army from the Normandy Beaches to the Bulge to the Surrender of Germany--and the opening of the American West--including Undaunted Courage: Meriwether Lewis, Thomas Jefferson, and the Opening of the American West and Nothing like It in the World: The Men Who Built the Transcontinental Railroad, 1863-1869. Ambrose, a "biographer and historian extraordinaire," according to Booklist's Nancy Spillman, has written about generals, presidents, explorers, major military battles, and foreign policy in his twenty-plus books, always demonstrating an uncommon ability to bring history and historical actors to vivid life.

Ambrose had already had a...