Catherine Of Lancaster

thumb|right|Arms of Catherine as Queen of Castile Catherine of Lancaster (Castilian: Catalina; 31 March 1373 – 2 June 1418) was Queen of Castile by marriage to King Henry III of Castile. She governed Castile as regent from 1406 until 1418 during the minority of her son. Queen Catherine was the daughter of John of Gaunt, 1st Duke of Lancaster, and his second wife, Constance of Castile (the eldest daughter and heiress of King Peter of Castile, who died at the hands of his half-brother Henry II).

She was born in Hertford Castle, her father's chief country home, on 31 March 1373. Catherine became Queen of Castile through her marriage to Henry III.