The king of Rome (rex Romae) was the ruler of the Roman Kingdom. According to legend, the first king of Rome was Romulus, who founded the city in 753 BC upon the Palatine Hill. Seven legendary kings are said to have ruled Rome until 509 BC, when the last king was overthrown. These kings ruled for an average of 35 years. The kings after Romulus were not known to be dynasts and no reference is made to the hereditary principle until after the fifth king Tarquinius Priscus. Consequently, some have assumed that the Tarquins' attempt to institute a hereditary monarchy over this conjectured earlier elective monarchy resulted in the formation of the Republic. Early Rome was ruled by the king (rex). The king possessed absolute power over the people; no one could rule over him. The Senate was a weak oligarchy, capable of exercising only minor administrative powers, so that Rome was ruled by its king who was in effect an absolute monarch. The Senate's main function was to carry out and administer the wishes of the king. After Romulus, Rome's first legendary king, Roman kings were elected by the people of Rome, sitting as a Curiate Assembly, who voted on the candidate that had been nominated by a chosen member of the Senate called an interrex. Candidates for the throne could be chosen from any source. For example, one such candidate, Lucius Tarquinius Priscus, was originally a citizen and migrant from a neighboring Etruscan city-state. The people of Rome, sitting as the Curiate Assembly, could then either accept or reject the nominated candidate-king. The king had twelve lictors wielding fasces, a curule chair which served as a throne, a purple toga picta, red shoes, and a white diadem worn on the head. Only the king could wear a purple toga. The supreme power of the state was vested in the king, whose position gave the following powers: Beyond his religious authority, the king was invested with the supreme military, executive, and judicial authority through the use of imperium.