Land reform efforts during the armed phase of the Mexican revolution (1910–20) remain largely overshadowed by the more dramatic events of the period. Based on records held in the Archivo General Agrario in Mexico City, this article shows how villagers in different parts of Mexico negotiated their claims to land with various revolutionary regimes during the armed struggle, with particular attention to the local committees created to measure land boundaries, conduct village censuses and distribute land. These negotiations between agrarian officials and villagers laid the foundations for the first post-revolutionary national administration. The emergent federal agrarian offices doubled as a legislative branch of government, assumed quasi-judicial functions and restricted the role of municipal and state governments – qualities that would characterise Mexico's agrarian reform for the next 70 years. In highlighting the ways that early land reform efforts contributed to state formation, this article questions the current social science inclination to ‘decentre’ Mexico's post-revolutionary regime.