Thomas de Berkeley, 5th Baron Berkeley 1417 he enfeoffed at Berkeley Castle, shortly before his death, several feoffees to hold all his lands in trust, due to the fact he had no male children as his heirs and that the course of succession then seemed unclear. The catalogue entry made by the British Museum librarian Isaac Jeaves for charter number 581 preserved in the muniments at Berkeley Castle records: The great City of London townhouse of the Berkeleys, known as "Berkeley's Inn", was at Puddle Dock by Baynard's Castle, close to the Blackfriars Monastery. Thomas FitzNicholl, one of the witnesses, was many times MP for Gloucestershire,
Margaret Mortimer, Baroness Berkeley Margaret Mortimer, Baroness Berkeley Margaret Mortimer, Baroness Berkeley (2 May 1304 – 5 May 1337) was the wife of Thomas de Berkeley, 3rd Baron Berkeley. She was the eldest daughter of Roger Mortimer, 1st Earl of March, the "de facto" ruler of England from 1327 to 1330, and his wife Joan de Geneville, Baroness Geneville. Margaret Mortimer was the eldest of the twelve children of Roger Mortimer, 1st Earl of March and Joan de Geneville, Baroness Geneville. Her paternal grandparents were Edmund Mortimer, 2nd Baron Mortimer and Margaret de Fiennes. Her maternal grandparents were Piers de Geneville, of Trim Castle