The legend of Romulus and Remus begins when their great grandfather Proca, the king of Alba Longa died. In his will he left his crown to his eldest son, Numitor, his younger brother, Amulius, wasn't happy with this arrangement and soon overthrew his brother and seized the crown for himself. In an attempt to ensure that he retained his throne Amulius murdered Numitor's sons and forced Numitor's daughter, Rhea Silvia, to become a vestal virgin (Vestal virgins were priestesses to the goddess Vesta and were expected to guard their virginity in the goddess' honour on pain of death), ensuring she would have no children.

The legends states that Mars, the god of war became enchanted by her beauty and has his way with her while she slept. Though the Romans were more inclined to believed that she was 'forcibly violated' and she named Mars as the father, either because she believed it, or the crime would seem less heinous if a deity was the cause of it. The result was that she had twin boys, Romulus and Remus.

Amulius was enraged and had Rhea Silvia thrown into prison and the boys thrown into the river Tiber. The river was in flood and the swampy surrounding land prevented a direct approach to the river itself and so the servants ordered to drown the boys decided that the stagnant water would be sufficient to drown the boys and so they left the boys in their cradle at a point of the overflow. The cradle floated down the stream until it caught in the branches of a fig tree and as the flood waters retreated the boys were left on dry land.

The cries of the boys attracted a thirsty she-wolf from the surrounding hills found the boys and suckled them (wolves are sacred to Mars) and was so gentle to them that when the king's flock master found the boys the wolf was licking the boys with her tongue. The shepherd, Faustulus, then took the boys to his hut and gave them to his wife Larentia, who had just lost a stillborn baby, to bring up.

Even the Roman's were dubious of the story of the wolf suckling the boys and it is believed that Larentia (the shepherd's wife) was a former prostitute (In Latin 'Lupa' means both she-wolf and prostitute) and it was her upbringing of the boys that led to the legend of the she-wolf suckling them.   

As the boys grew up they too became shepherds but they loved hunting and would often hunt beasts of prey but would also even attack brigands when loaded with their plunder. They would distribute the gains they made from this amongst the shepherds and an increasing number of young men started to associate themselves with the two boys.

One year the boys participated in the festival of the Lupercalia (an Arcadian festival in which young men run around naked in honour of Pan) when brigands decided to ambush them. Romulus managed to defend himself and escape but Remus was captured and taken before king Amulius as the brigands accused him of their own crimes. Remus was handed over to Numitor (his grandfather) for punishment. Faustulus had always suspected that Romulus and Remus had royal blood as his finding of them coincided with the exposure of Numitor's grandchildren and in his alarm for Remus's safety he told this to Romulus. In the palace after questioning Remus about himself and his brother he soon reached the conclusion that that Remus was his grandchild.

Not daring to make a direct assault on the city Romulus and his shepherds snuck into the city and met at the palace at a given time, Remus (with Numitor's help presumably) had also gathered a body of men to his cause. Just before the attack Numitor told the army that that the city was under attack and that they should go to the citadel to defend it leaving Romulus and Remus easy passage to the king who they promptly killed.

Numitor gathered the people of Alba Longa together and explained the veils f his brother, who the boys were and how he and the boys had killed Amulius. Romulus and Remus then marched up to their grandfather and saluted him as king. The population agreed and Numitor was restored to his throne. Romulus and Remus decided they wanted to found a new city on the site of where they had been exposed and so they took their shepherds and some excess population from the Latin towns to build the town.

As the boys were twins no precedence of seniority could be set by age so they decided to use augury to determine who would give the name to the new city and who would rule it once it was built. Romulus climbed the Palantine hill as his station of observation and Remus the Aventine. Remus received an omen first when six vultures appeared before him. This augury had just been announced to Romulus when twelve vultures appeared before him. Each was saluted as king by his own party. One side because of the priority of appearance the other because of the number of birds. Soon a fight started and Remus was killed.

There is a second and more commonly known version that states that Romulus had walls built on the Palantine hill and Remus contemptuously jumped over these walls which enraged Romulus who then killed his brother and exclaimed "So shall it be henceforth with anyone who leaps over my walls" so Romulus became sole ruler and the city was called after him, its founder.