Maurice de Berkeley Maurice de Berkeley Sir Maurice de Berkeley "the Resolute" (1218 - 4 April 1281), 5th (feudal) Baron de Berkeley, was an English soldier and rebel, residing at Berkeley Castle in the English county of Gloucestershire. Maurice was born in 1218 to Thomas de Berkeley and Joan de Somery. He married Isabel FitzRoy, the daughter of Richard FitzRoy, Baron of Chilham (an illegitimate son of King John of England) and Rose de Douvres, sometime before 12 July 1247. Berkeley fought in the French Wars and was invested as a knight before 1242. He inherited the title of Baron de Berkeley in
Thomas de Berkeley, 5th Baron Berkeley to that of his contemporary Sir Maurice Russell (d.1416) at Dyrham, who was the father-in-law of Gilbert Denys, one of Berkeley's feoffees. Having died without male progeny the succession to the vast Berkeley estates became disputed, and eventually resulted in the Battle of Nibley Green (1469/70), the last battle fought in England entirely between the private armies of feudal magnates, fought near Berkeley Castle on 20 March 1469/70 between the troops of Thomas Talbot, 2nd Viscount Lisle and William Berkeley, 2nd Baron Berkeley, later 1st Marquess of Berkeley. Lisle and William Berkeley had long been engaged in a dispute over