Lucius, who was half Etruscan and half Greek, was a tyrant. As a result of Lucius' conduct, he earned the nickname of 'Superbus'. He deprived his father-in-law, Servius Tullius, of burial, on the plea that Romulus was not buried, and he slew the leading nobles whom he suspected of being supporters of Servius. He was the first of the kings to break through the traditional custom of consulting the senate on all questions, and the first to conduct the government on the advice of his palace favorites. War, peace, treaties, alliances were made or broken off by him. He gave his daughter in marriage to Octavius Mamilius of Tusculum.

Tarquin the Proud was the last King that was called a 'Rex' at the time, to rule over Etruscan Rome. He was a tyrannical King who used his authority for his own self- interest and not for the good of the people. It was his rule as the King of Etruscan Rome, the actions of his son, Sextus Tarquinius, and the actions of Brutus, that saw the end of the rule of Kings in Etruscan Rome. It also saw the development of a political system with elected leaders.

The first Etruscan Kings that ruled Rome were not seen as tyrants and were even credited with helping to make Rome a better place. This changed during the rule of Tarquin the Proud. He was only interested in his own self being and used his status to exploit his people to boost his worth. He took land from many of the patrician nobles and sent many of them to death. Lucius Tarquinius Superbus reigned twenty-five years.

Tarquin the Proud's selfish and tyrannical behavior helped to inspire Brutus to over-throw the existing system of government and it also led to the eventual exile of him and his family from Rome. The actions of Tarquin's son, who was much like his father was also a factor. As the legend tells, Tarquin the Proud's son, Sextus Tarquinius was also a selfish man who took what he wanted.

The story goes that when he was invited to a friend's house, Collatinus, Sextus met Collatinus's wife Lucretia, whom he immediately fell in love with. Lucretia was the example of the perfect Etruscan women; she was true, honest and she had her most important attribute, her virtue. A few nights later when Collatinus was not around, Sextus went to Lucretia's place and stayed as a houseguest. Later that night Sextus, who had to have what he wanted, went into Lucretia's room and raped her.

When Collatinus and Lucretia's father heard of this they were destroyed. In response to her losing her virtue and everything she believed in, Lucretia killed herself with a dagger. The Romans drove Tarquin the Proud from the throne (510 B.C.). Lars Porsena , the Etruscan king of Clusium, considered that the presence of an Etruscan upon the Roman throne would be an honor to his nation; accordingly he advanced with an army against Rome. He tried to restore the family; failing, he made peace with Rome.

Brutus, who also witnessed Lucretia's demise, drew the dagger from her, put it in the air and vowed that there would never be another tyrannical king ruling in Rome. It would be the actions that Brutus would carry out after this, that would see the fall of the king system and development of a more democratic system. Thus began the age of the Roman Republic.