This book examines the characteristics of political power in the cities of the colonial Spanish Empire between the 1740s and 1780s, based on a detailed study of the mining city of Oruro in Alto Peru (present-day Bolivia). Special emphasis is given to the specific forms of the exercise of power, assessing in particular the workings of the judicial system and the material opportunities that were open to different bureaucratic officials. Towards the end of this period, the analysis focuses on the Indian uprisings of the 1780s (the rebellions of Tupac Amaru) and the reasons which led to the alliances or confrontations between the actors of the distinct bands, either white or Indian.