On July 9, 1755, British and colonial troops under the command of General Edward Braddock suffered a crushing defeat to French and Native American enemy forces. The Battle of the Monongahela altered the trajectory of the Seven Years' War in America, greatly escalating the war and inexorably defining its military and political character. The Monongahela was an unprecedented rout of a modern and powerful British army by a predominantly Indian force, and as David Preston shows in this gripping new account, no other battle before 1775 had such a searing effect on the colonial British world. The culmination of a failed attempt to capture Fort Duquesne from the French, Braddock's Defeat was a pivotal moment in American and world history, ranking with the destruction of Varus's legions in the Teutoburg Forest, Noche Triste, St. Clair's Defeat, and the Little Bighorn as examples of imperial forces falling to indigenous foes. While the defeat is often said to have been caused by blundering and arrogance on the part of Braddock, Preston argues that this myth has depreciated the victory that Indian and French forces won by their superior discipline, tactical decisions, and leadership. The French Canadian officer Captain Beaujeu had greater tactical skill, better reconnaissance, and a battle plan that he effectively coordinated with Indian allies who brilliantly executed it, Preston shows. The Indians were the most effective and disciplined troops on the field on that decisive July day, especially in comparison to Braddock's poorly trained, amalgamated, and ultimately undisciplined Regulars. Reframing our understanding of the superiority of the French and Indian alliance, Preston also explores the long shadow cast by Braddock's Defeat over the 18th century and the American Revolution. The campaign had been an awakening to empire for many British Americans, spawning a sustained discourse on American identity and anticipating many of the empire's political and social divisions that became wider and deeper by the outbreak of the Revolution. It was the defining generational experience for many of British and American officers, including George Washington, Thomas Gage, and Horatio Gates, who carried their veteran experiences from the Seven Years' War forward into American Revolution. Rooted in extensive fieldwork on the campaign's geography and terrain and presenting an abundance of new evidence, Braddock's Defeat presents the fullest account yet of this defining moment in early American history.