William Ros, 1st Baron Ros
William Ros or Roos, 1st Baron Ros of Helmsley (c. 1255 – 6 or 8 August 1316), was one of the claimants of the crown of Scotland in 1292 during the reign of Edward I. Family William Ros was the eldest son of Robert de Ros (d. 17 May 1285) of Helmsley, Yorkshire, and Isabel d'Aubigny (c. 1233 – 15 June 1301), daughter and heiress of William D'Aubigny of Belvoir, Leicestershire, and granddaughter of William d'Aubigny. He had four brothers and three sisters: Sir Robert Ros of Gedney, Lincolnshire. John Ros. Nicholas Ros, a cleric. Peter Ros, a cleric. Isabel Ros, who married Walter Fauconberg, 2nd Baron Fauconberg. Joan Ros, who married John Lovel, 1st Baron Lovel, as his second wife. Mary Ros, who married William de Braose, 1st Baron Braose. Career On 24 December 1264, William's father, Robert de Ros (d. 1285), was summoned to Simon de Montfort's Parliament in London as Robert de Ros, and for some time it was considered that the barony was created by writ in that year, and that Robert de Ros was the 1st Baron Ros. According to The Complete Peerage: In 1616, the barony of Ros was allowed precedence from this writ