During the formation of the Mexican nation, jefaturas políticas, or prefectures, as they will be called generically in this article, were basic institutions (1812–1917) for centralizing and organizing power and assuring governance. This was a vital task given the civil and international wars the country would endure. These powerful institutions were the mediators between the upper and lower political echelons and social classes. In the prefectures were vested an impressive range of diverse responsibilities—agrarian, fiscal, preserving order, military conscriptions, educational, medical and sanitary services, promoting the economy, elaborating statistics, mapmaking—which made modernization and administrative functionality very difficult. At the turn of the 20th century, this was an obstacle to the modernization and efficacy of the regime. Even though prefectures had responsibilities for all of Mexico, they also had an important degree of flexibility to attend to local needs. Therefore, laws and practices were adapted to the peculiarities of the different states, for example, regulating labor or conciliating rivalries that sprang from the application of liberal agrarian policies. Prefects governed specific political districts in which the states were divided and were generally appointed and removed freely by the governors as their personal representatives to enforce laws and policies and to control any opposition. They were remembered in popular imaginary, literary, and revolutionary historiography as brutal and corrupt functionaries loyal only to the upper classes and their clientelist networks. Contemporary studies have proved that these modalities—brutality and corruption—have a place in the prefect’s box of tools, but new research has widened the historiographic perspective and showed how differently these functionaries could act. In fact, they used most of their energy trying to negotiate with the whole range of social classes and political factions. But their repressive character led to its elimination: they fought the revolution of 1910, and when they lost they were suppressed in 1917.