Robert E. Lee

March 9–29, 1847 · 1,880 total casualties

The capture of Veracruz opened the National Highway to Mexico City and demonstrated American capability for large-scale combined arms operations. Robert E. Lee served as an engineer officer here, beginning to earn the reputation for bold reconnaissance that would define his career. The siege established Scott's campaign as the war-winning strategic thrust.

April 17–18, 1847 · 1,631 total casualties

Cerro Gordo was a masterpiece of reconnaissance-based flanking maneuver. Lee's engineering brilliance became the talk of the army. The battle opened the road to Jalapa and the Valley of Mexico and shattered Santa Anna's army, though he would regroup and fight on. The pattern of bold flanking movements Lee employed here would echo through his Civil War campaigns.

August 19–20, 1847 · 760 total casualties

Contreras removed the final obstacle south of Mexico City and demonstrated again the decisive value of engineer reconnaissance. The rapid victory preserved American momentum and prevented Valencia from reinforcing the stronger Mexican positions at Churubusco. Winfield Scott famously praised Lee's work at Contreras as the greatest feat of arms of any officer in the campaign.

August 20, 1847 · 5,349 total casualties

Churubusco's heavy casualties led Scott to accept an armistice to negotiate, which ultimately failed but gave Mexico time to regroup. The battle effectively cleared the approaches to Mexico City. The captured members of the San Patricio Battalion were court-martialed and many hanged, in one of the war's most controversial episodes.

September 13, 1847 · 2,662 total casualties

The storming of Chapultepec is remembered as the decisive battle of the war and one of the most celebrated actions in U.S. Marine Corps history ('the Halls of Montezuma'). The fall of the castle opened the causeways into Mexico City. The Niños Héroes became enduring heroes of Mexican national memory. Within hours, Scott's army entered the capital.

September 13–14, 1847 · 3,862 total casualties

The occupation of Mexico City effectively ended the war. With their capital fallen and their army shattered, Mexican political leaders had no choice but to negotiate. The occupation lasted until June 1848, when the Treaty of Guadalupe Hidalgo was ratified and American forces withdrew. The campaign from Veracruz to Mexico City over 260 miles against superior numbers is studied at military academies worldwide.