New Constitution and Carranza's Policies
In 1916 the Carrancistas convened a constitutional assembly in the city of Querétaro, approving a new constitution on February 5, 1917. One of the mainstays of the new constitution was Article 27, which established the authority of the Mexican state over soil and subsoil, creating a juridical foundation for agrarian reform (and, much later, state control of mineral resources). Article 27 recognized diverse forms of land tenure: farmer and campesino smallholdings, village ejidos (commons), and indigenous communal lands. If the Carrancista leadership hoped that Article 27 would create a legal channel for agrarian demands, however, the article only served to legitimate agrarian mobilizations. Between 1917 and 1920 the Carranza government tried to circumvent Article 27, freezing land redistribution, returning haciendas expropriated during the Revolution to their former owners, and continuing the war against the remnants of the Villista forces and the Zapatistas in the southern part of the country; on April 10, 1919, Emiliano Zapata was assassinated in a government ambush.

Nonetheless, Carranza's policies only served to alienate his agrarian base of support. Drawing on the support of agrarian revolutionaries, the military rebellion of Agua Prieta overthrew the Carranza government in 1920, establishing an interim government under Adolfo de la Huerta; the leader of the revolt, Álvaro Obregón, later was elected president, serving in office between 1921 and 1924. During the revolt Obregón had cut a deal with the Zapatistas, and once in power he acceded to many of their agrarian demands in Morelos. Even after defeat agrarian forces continued to influence the destiny of the Mexican nation.

At the start of the Revolution in 1910 there were 8,431 haciendas and 48,633 ranchos in existence, making a total of 57,064 properties; 96.9 percent of the heads of rural families, however, owned no land at all. Historian Frank Tannenbaum cites some examples of this concentration of landed property: three haciendas occupied the 200 miles (300 kilometers) between the cities of Saltillo and Zacatecas; the Terrazas family properties in Chihuahua encompassed as much land as the entire nation of Costa Rica; in the state of Hidalgo the railway ran 100 miles (150 kilometers) without leaving the properties of the Escandón family; foreign companies owned 78 percent of the land in Baja California; and the Hearst family owned 30,000 square miles (77,700 square kilometers) in Chihuahua, the largest latifundium in the country.