His brother, Numitor, was the King of Alba Longa. Amulius overthrew him, killed his sons, and took the throne. Amulius forced Rhea Silvia, Numitor's daughter, to become a Vestal Virgin, a priestess of Vesta, so that she would never bear any sons that might overthrow him. However, she was raped or seduced by the god Mars, resulting in the birth of Romulus and Remus. Amulius had Rhea Silvia thrown into prison and her sons into the river Tiber, as he determined she had violated her oaths of chastity. The twins washed up onto dry land and were found by a she-wolf who suckled them. Later their mother was saved by the river god Tiberinus who ended up marrying her. Romulus and Remus went on to found Rome and overthrow Amulius, reinstating their grandfather Numitor as king of Alba Longa.