Romulus was a demigod son of Mars and the founder of Rome. His mother was Rhea Silvia and was the twin brother of Remus.
His mother was the daughter of Numitor, king of Alba Longa. Before he and his brother's conception, Numitor's brother Amulius seizes power, kills Numitor's male heirs and forces Rhea Silvia to become a Vestal Virgin, sworn to chastity. Rhea Silvia conceives the twins by the god Mars. Once the twins were born, Amulius had them abandoned to die in the river Tiber. They were saved by a series of miraculous interventions: the river carried them to safety, a she-wolf (in Latin, lupa) found and suckled them, and a woodpecker fed them.
A shepherd and his wife found them and fostered them to manhood, as shepherds. The twins, unaware of their true origins, proved to be natural leaders. Each brother acquired many followers. When they discovered the truth of their birth, they killed Amulius and restored Numitor to his throne. Rather than wait to inherit Alba Longa, they choose to found a new city.
Romulus wanted to found the city on the Palatine Hill; Remus prefered the Aventine Hill. They agreed to determine the site through augury but when each claimed the results in his own favor, they quarrel and Romulus killed Remus. Romulus founded the city, naming it Rome, after himself, and created its first legions and senate.
The new city grew rapidly, swelling by landless refugees; as most of these are male, and unmarried, Romulus arranges the abduction of women from the neighboring Sabines. The ensuing war ends with the joining of Sabines and Romans as one Roman people. From divine aid and Romulus' inspiring leadership, Rome became a dominant force, but Romulus himself became increasingly autocratic. In his old age he ascended to Olympus, becaoming Quirinus, a patron of the Roman people.