This thesis studies the political role of the Chilean military during the years 1780-1826. Beginning with the last decades of the eighteenth century and ending immediately after the last royalist contingents were expelled from the island of Chiloé, this thesis does not seek to give a full picture of the participation of military men on the battlefield but rather to interpret their involvement in local politics. The main categories deployed in this study are 1) armies, 2) politics and 3) revolution, and the three are presented with the purpose of demonstrating that, as Peggy K. Liss has claimed, after 1810 Spanish American public life ‘became militarized; and the military, privileged’. I argue that, notwithstanding the sometimes tense relationship between civilians and the armed forces, the Chilean military became privileged because the demise of the Spanish monarchy in 1808 made them protagonists of the decision-making process. In so doing, this thesis aims to make a contribution to the understanding of Chile’s revolution of independence, as well as to discuss some recent historiographical contributions on the role of the military in the creation of the Chilean republican system. Although the focus has been placed on the career and participation of Chilean revolutionary officers, this thesis also seeks to provide an overview of both the role of royalist armies and the influence of international events in Chile.