This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Mexico's 1917 constitution, adopted in the wake of the Mexican Revolution, placed sweeping restrictions on the Catholic Church: it barred religious orders, stripped the Church of the right to own property, denied clergy the vote and forbade them from criticizing the government or wearing clerical dress in public. For nearly a decade these provisions were enforced unevenly, but in June 1926 President Plutarco Elias Calles began enforcing them with new severity, limiting the number of priests permitted to practice and requiring their registration with the state. The Mexican bishops responded by suspending public worship across the country in protest.
Armed resistance broke out first in Jalisco and spread through the west-central Mexican states of Michoacan, Guanajuato and Zacatecas. Rebels, who came to be called Cristeros for their battle cry "Viva Cristo Rey," organized locally around parish networks and were loosely coordinated by a lay organization, the Liga Nacional Defensora de la Libertad Religiosa; the Catholic hierarchy itself never officially sanctioned the uprising, even as individual priests supported or fought alongside it. Federal troops under Calles, and after 1928 under his successor Emilio Portes Gil, fought a grinding counterinsurgency across the region for nearly three years.
The war ended not in military victory for either side but in a negotiated settlement, the Arreglos of June 1929, brokered with the involvement of United States ambassador Dwight Morrow. The Church resumed public worship; the anticlerical constitutional provisions that had provoked the war were not repealed. Sporadic killings of amnestied Cristero fighters continued for a period afterward, and the underlying tension between the Mexican state and the Church persisted for years to come.