Thomas de Berkeley, 1st Baron Berkeley Thomas de Berkeley, 1st Baron Berkeley Thomas de Berkeley, 1st Baron Berkeley (c.1251 – 23 July 1321), "The Wise", feudal baron of Berkeley, of Berkeley Castle in Gloucestershire, England, was a peer, soldier and diplomat. His epithet, and that of each previous and subsequent head of his family, was coined by John Smyth of Nibley (d.1641), steward of the Berkeley estates, the biographer of the family and author of "Lives of the Berkeleys". Thomas de Berkeley was born around 1251 at Berkeley Castle in Gloucestershire, the son of Sir Maurice de Berkeley, feudal baron of Berkeley, by his wife Isabel
Berkeley Castle around 1067 by William FitzOsbern shortly after the Conquest. This was subsequently held by three generations of the first Berkeley family, all called Roger de Berkeley, and rebuilt by them in the first half of the 12th century. The last Roger de Berkeley was dispossessed in 1152 for withholding his allegiance from the House of Plantagenet during the conflict of The Anarchy, and the feudal barony of Berkeley was then granted to Robert Fitzharding, a wealthy burgess of Bristol and supporter of the Plantagenets. He was the founder of the Berkeley family which still holds the castle. In 1153–54, Fitzharding