Infante Dinís, Lord of Cifuentes

Denis of Portugal, occasionally surnamed Castro, was an infante of Portugal. He was the son of Portuguese King Peter I and a Galician noblewoman named Inês de Castro who had arrived in Portugal as a maid of princess Constance of Castile, recently married to Pedro I. Peter and Inês were not married at the time of Denis birth but Peter had him and his siblings legitimized once he became king.