Praefectus vigilum

The praefectus vigilum (lit. 'prefect of the watchmen', pl.: praefecti vigilum) was, starting with the reign of the Emperor Augustus, the commander of the city guards in Rome (cohortes vigilum or vigiles), whom were responsible for maintaining peace and order at night--a kind of fire and security police. Although less important than the other prefects, the office was considered a first step in order to reach an important position in the imperial administration.