William de Berkeley, 1st Marquess of Berkeley William de Berkeley, 1st Marquess of Berkeley William de Berkeley, 1st Marquess of Berkeley (1426 – 14 February 1492) was an English peer, given the epithet "The Waste-All" by the family biographer and steward John Smyth of Nibley. He was buried at "St. Augustine's Friars, London" according to one source, but most likely in the Berkeley family foundation of St Augustine's Abbey, Bristol. William of Berkley was born to James Berkeley, 1st Baron Berkeley, and Lady Isabel Mowbray at Berkeley Castle in Berkeley, Gloucestershire, in 1426. His first marriage was in 1466 to Elizabeth West, daughter of Reginald West, 6th
James Berkeley, 1st Baron Berkeley cousin Elizabeth, daughter of the fifth Baron Berkeley and wife of Richard de Beauchamp, 13th Earl of Warwick. He was unable initially to claim Berkeley Castle, as it was taken in possession by the Earl and Countess of Warwick. In 1421, when the Warwicks finally gave up Berkeley Castle, James was summoned to Parliament by writ as Lord Berkeley. The feud did not end there as his third wife Isabel was captured by the Countess of Warwick's son-in-law the Earl of Shrewsbury, and held imprisoned until her death in 1452. Lord Berkeley was succeeded by his son from his third