The Battle of Celaya, 6–15 April 1915, was part of a series of military engagements in the Bajío during the Mexican Revolution between the winners, who had allied against the regime of Gen. Victoriano Huerta (February 1913-July 1914) and then fought each other for control of Mexico. The Constitutionalists under Gen. Venustiano Carranza faced off against the Army of the División del Norte of Pancho Villa. The first battle of Celaya was fought April 6–7, 1915, near Celaya in present-day Guanajuato, Mexico. The second battle of Celaya was fought April 15–16. These encounters between the Constitutionalist Army led by Gen. Álvaro Obregón, Venustiano Carranza's best general, and the army under the command of Pancho Villa were crucial in determining the outcome of the Mexican Revolution.