A consul was the highest elected public official of the Roman Republic (c. 509 BC to 27 BC). Romans considered the consulship the second-highest level of the cursus honorum—an ascending sequence of public offices to which politicians aspired—after that of the censor, which was reserved for former consuls. Each year, the Centuriate Assembly elected two consuls to serve jointly for a one-year term. The consuls alternated each month holding fasces (taking turns leading) when both were in Rome. A consul's imperium (military power) extended over Rome and all its provinces. There were two consuls in order to create a check on the power of any individual citizen in accordance with the republican belief that the powers of the former kings of Rome should be spread out into multiple offices. To that end, each consul could veto the actions of the other consul. After the establishment of the Empire (27 BC), the consuls became mere symbolic representatives of Rome's republican heritage and held very little power and authority, with the Emperor acting as the supreme authority. Source: Wikipedia (en)