Tribune () was the title of various elected officials in ancient Rome. The two most important were the tribunes of the plebs and the military tribunes. For most of Roman history, a college of ten tribunes of the plebs acted as a check on the authority of the senate and the annual magistrates, holding the power of ius intercessionis to intervene on behalf of the plebeians, and veto unfavourable legislation. There were also military tribunes, who commanded portions of the Roman army, subordinate to higher magistrates, such as the consuls and praetors, promagistrates, and their legates. Various officers within the Roman army were also known as tribunes. The title was also used for several other positions and classes in the course of Roman history. Tribal tribunes The word tribune is derived from the Roman tribes. The three original tribes known as the Ramnes or Ramnenses, Tities or Titienses, and the Luceres, were each headed by a tribune, who represented each tribe in civil, religious, and military matters. Subsequently, each of the Servian tribes was also represented by a tribune. Tribune of the celeres Under the Roman Kingdom, the tribunus celerum, in English tribune of the celeres, or tribune of the knights, was commander of the king's personal bodyguard, known as the celeres. This official was second only to the king, and had the authority to pass law, known as lex tribunicia, and to preside over the comitia curiata. Unless the king himself elected to lead the cavalry into battle, this responsibility fell to the tribune of the celeres. In theory he could deprive the king of his imperium, or authority to command, with the agreement of the comitia curiata. In the reign of Lucius Tarquinius Superbus, the last Roman king, this office was held by Lucius Junius Brutus, the king's nephew, and thus the senior member of the king's household, after the king himself and his sons. It was Brutus who convened the comitia and asked that they revoke the king's imperium. After the fall of the monarchy, the powers of the tribune of the celeres were divided between the Magister Militum, or Master of the Infantry, also known as the Praetor Maximus or dictator, and his lieutenant, the magister equitum or "Master of the Horse". Tribune of the plebs The tribuni plebis, known in English as tribunes of the plebs, tribunes of the people, or plebeian tribunes, were instituted