The Battle of Celaya on the 13th of April 1915 was the single bloodiest battle of the Mexican Revolution. The Conventionist forces under Pancho Villa were badly defeated by forces under the command of Álvaro Obregón, who supported the presidency of Venustiano Carranza. Villa lost around 4,000 men killed in frontal attacks. 1915 was a common year starting on Friday (see link for calendar). ... The Mexican Revolution, sometimes called the Mexican Revolution of 1910, was a violent social and cultural movement, colored by socialist, nationalist, and anarchist tendencies, that began with the popular rejection of dictator Porfirio Díaz Mori in 1910 and continued even after the promulgation of a new constitution seven years... General Pancho Villa José Doroteo Arango Arámbula (June 5, 1878 – July 20, 1923) — better known by his nom de guerre Francisco Villa or, in its diminutive form, Pancho Villa — was one of the foremost leaders of the Mexican Revolution. ... Term of office: 1 December 1920 – 1 December 1924 Preceded by: Adolfo de la Huerta Interim Succeeded by: Plutarco Elías Calles Date of birth: 19 February 1880 Place of birth: Navojoa, Sonora Date of death: 17 July 1928 Place of death: Mexico City Profession: Military First Lady: María... Venustiano Carranza Garza (29 December 1859 - 21 May 1920) was one of the leaders of the Mexican Revolution. ...

In this battle, Obregón developed a wise defense "in depth" that proved very effective against the cavalry charges and artillery techniques used at that time. This battle was a turning point in the future of Villa, the Revolution and Mexican history in the 20th century.