Tarquin the Proud was the last king in ancient Rome. He was not a good king. He was a tyrant and the people hated him. There is not a set tale of how the Romans actually got rid of him, but there is an important story that tells about their war with him. That story is "Horatius at the Bridge".
Whether the story is true or not, it is important because it enhanced the reputation of Rome and the Roman Legions. It told other people that Rome was loved and protected by the gods.
As the story goes ...
A very long time ago the city of Rome was ruled by kings. Sometimes these kings were Roman, sometimes these kings were Etruscan. At the time of this legend, the Romans were ruled by an Etruscan king called Tarquin the Proud. Tarquin was a terrible king. He was cruel and unjust. The Roman people revolted against Tarquin and defeated him. They then exiled him back to the Etruscan league. Tarquin went to the Etruscan league and asked for help. Seeing how rich Rome was, the Etruscans decided to help so that they could get hold of the Roman riches. They sent their army with Tarquin to conquer Rome.
Rome was surprised that the Etruscans had decided to help Tarquin. They hadn't gotten their army back together yet. The farmers and villagers living outside of Rome saw the advancing army and fled into the city of Rome for protection. One of Rome's best natural defenses was the Tiber river. If the Romans could get their people across the bridges over the Tiber, then knock down the bridges, they would be safe from Tarquin.
The Roman commanding general had forgotten about the bridges while he was getting his army ready to fight the Etruscans. On their own, Romans knocked down most of the bridges over the Tiber. But one bridge still stood. Tarquin saw the bridge and sent his army rushing towards it. Guarding the bridge were several Roman soldiers. They were too few to stop the Etruscan army, yet all knew if they didn't stop the Etruscans and knock down the bridge, the city of Rome was doomed.
One Roman soldier named Horatius was determined to stop the Etruscans. He tried to get other soldiers to help him defend the bridge while giving time to other soldiers to knock the bridge down. The rest of the soldiers were too afraid to go onto the bridge with Horatius, so he went alone. There he was, alone on the bridge with the entire Etruscan army coming after him. Horatius stood his ground. The bridge was too narrow for many Etruscan soldiers to attack Horatius at once. Horatius was a very skilled soldier. He fought the Etruscans and stopped the advance. Sooner or later though, Horatius would have to retreat or die. The other Roman soldiers began knocking down the bridge supports. Horatius felt the bridge starting to fall into the river, and he dove into the Tiber river and swam back to Rome. The Etruscans were stopped. Horatius was a hero.
We don't know if this story is true, or if it was made up to show the rest of the world how brave and skilled Roman soldiers were. But it is pretty good story.