Only a decade after the onset of Mexico's 1910 revolution, the people of Monterrey, Nuevo León could celebrate the class harmony that reigned in their preeminently industrial city. The regiomontanos attributed this aura of industrial peace to the unique character of their city's workers and the inherent benevolence of their employers. They took special pride in both. Monterrey's workers carried a reputation for their hard work, industriousness, and staunch independence. They manifested the latter through their renowned autonomy from the national unions organized in the revolution's wake. The industrialists earned local acclaim for having built their companies with Mexican capital. Moreover, such pillars of local industry as the Cuauhtémoc Brewery and the Fundidora steel mill provided their employees with welfare benefits unique by Mexican standards. Since the early 1920s, civic boosters insisted, company paternalism had established the cornerstone of labor peace and economic prosperity. Then, just as General Lázaro Cárdenas assumed the presidency in 1935, class struggle seemingly engulfed their hometown. In a startling development, the steel workers broke from the Independent Unions of Nuevo León and affiliated with the national Miner-Metalworkers Union. Ten days later, workers at the brewery's subsidiary glass plant, Vidriera Monterrey, struck in support of militant unionism.

The industrialists blamed this outbreak of militance on the Cárdenas government's intrusive labor policies. Indignant at this perceived threat to their social hegemony, the industrialists orchestrated a mass antigovernment rally. They punctuated their resistance with a two-day lockout, shutting down their factories in a display of economic might.