"Violence on a limited scale occurred throughout the early 1920s, but it never rose to the level of widespread conflict.In 1926, the passage of stringent anticlerical criminal laws and their enforcement by the so-called Calles Law, together with peasant revolts against land reform in the heavily-Catholic Bajio and the clampdown on popular religious celebrations such as fiestas, caused scattered guerrilla operations to coalesce into a serious armed revolt against the government.