Peter I of Portugal, also known as Peter the Just, was the King of Portugal from 1357 until his death in 1367. He was the son of Afonso IV of Portugal and Beatrice of Portugal. Peter is remembered for his efforts to strengthen the monarchy and improve the legal system, earning him a reputation for justice and fairness. Peter I is also famous for his tragic love story with Inês de Castro, a noblewoman he secretly married. After her murder, Peter sought vengeance against those responsible and posthumously declared her queen, symbolizing his deep devotion and the complexities of love and power in medieval Portugal.