The overthrow of Viceroy Joaqu&ín de la Pezuela on 29 January 1821 has not received much attention from historians, who have viewed it as a simple military uprising. Yet in this careful study of the episode, based on deep archival research, Patricia Marks reveals it to be the culmination of decades of Peruvian opposition to the Bourbon reforms of the late eighteenth century, especially the Reglamento de comercio libre of 1778. It also marked a radical change in political culture brought about by the constitutional upheavals that followed Napolean's invasion of Spain. Although Pezuela's overthrow was organized and carried out by royalists among the merchants and the military, it proved to be an important event in the development of the independence movement as well as a pivotal factor in the failure to establish a stable national state in post-independence Peru. The golpe de estado may thereby be seen as an early manifestation of Latin American praetorianism, in which a sector of the civilian population, unable to prevail politically and unwilling to compromise, pressures army officers to act in order to &"save&" the state.