Eutropius

“ XIII In the sixteenth year after the termination of the regal power, the people at Rome, thinking themselves oppressed by the senate and consuls, broke out into a sedition. On this occasion they created for themselves tribunes of the people, as their own peculiar judges and defenders, by whom they might be protected against the senate and the consuls.
XIV In the following year the Volsci recommenced hostilities against the Romans; and being overcome in the field, lost also Corioli, the best city that they had. ”

“ He was the first to institute the census, which till that time was unknown throughout the world. The people being all subjected to a census during his reign, Rome was found to contain eighty-four thousand citizens, including those in the country. He was cut off in the forty-fifth year of his reign, by the criminal machinations of his son-in-law Tarquin the Proud, the son of the king to whom he had succeeded, and of his own daughter, whom Tarquin had married. ”

“ It was determined also that they should not hold their office longer than a year; in order that they might not, by continued possession of power, grow too overbearing; but, knowing that in a year they would return to the level of private persons, might constantly conduct themselves with moderation.
In the first year, then, after the expulsion of the king and his family, the consuls were Lucius Junius Brutus, who had been the chief agent in the banishment of Tarquin, and Tarquinius Collatinus, the husband of Lucretia. ”