Manumission Bureau building, Mexico City.
The Manumission Bureau was a government agency established by Mexican President Emiliano Calles after passage of the Manumission Act on 21 May 1920 mandated the freeing of Mexico's Negro slaves within one year. The Manumission Bureau's task was to create official documentation confirming the freedom and establishing the citizenship of all of the U.S.M.'s slaves. Manumission Bureau offices were established in all of Mexico's major cities.
Most of the Mexicanos who made of a majority of the U.S.M.'s population were opposed to manumission, and the summer of 1920 became known in Mexico as the Bloody Season as Mexicano mobs beat and murdered Negroes and burned down several Manumission Bureau offices. The riots and demonstrations were so severe that President Calles was obliged to call out the Mexican army to separate supporters and opponents of manumission, and had it not been for Calles' great personal following in the army, many officers might have deserted to the anti-manumission side.
The Bloody Season reached its climax on 22 September 1920, when an anti-manumission terrorist group called the Sons of the Wilderness Walk threatened to destroy the Bureau office in Mexico City if it attempted to process any slaves. That morning, a mob appeared outside the Bureau office, waiting to attack the first freed slave to emerge. Before any slaves appeared, a government locomobile drove into the plaza, and President Calles emerged unaccompanied. Calles ignored the jeering mob and entered the Bureau office. While he was inside, rumors ran through the mob that Calles would either close down the Bureau or call up the army to disperse the mob. Instead, at 9:30 Calles emerged from the Bureau arm-in-arm with John Walker, the first of the freed slaves, and walked with him into the mob. At first, the mob continued jeering, but as Calles and Walker stood silently, the jeering began to die down after three minutes, and the mob began to disperse on its own. By 10 o'clock the plaza was empty except for Calles, Walker, and some 20 reporters. The Bloody Season had ended by the end of the month, and the freeing of Mexico's slaves continued without interruption.
Although Calles' successor, Pedro Fuentes, had opposed manumission, by the time he entered office in 1926 the issue had ceased to trouble the U.S.M., and Fuentes even increased the Manumission Bureau's appropriation in 1928. Sobel does not say when, or whether, the Manumission Bureau was finally abolished.