During the period of the Mexican Revolution, Ricardo Flores Magón and the Mexican Liberal Party built the first significant cross-border organization dedicated to international solidarity and anti-capitalism. Magonismo also became the foundation for radical politics for Mexican and Chicano working class movements in the United States. This talk will explore the development and evolution of Magonismo in the context of the rising workers' movement, the Mexican Revolution, and the cross-border experiences of Mexican workers in the United States.