Robert Fitzwalter was the only son of Sir Walter FitzRobert of Woodham Walter, Essex , son of Robert Fitzwalter, and Ida II Longespée, daughter or granddaughter of William Longespée, 3rd Earl of Salisbury, illegitimate son of Henry II. In 1258 his wardship was granted to his uncle, Sir Stephen Longespée. He came of age in 1268, and was knighted in 1274. In 1275, he had licence to sell Baynard's Castle in London to Robert Kilwardby, Archbishop of Canterbury. In 1277, and again in 1282, he took part in the wars in Wales. in February 1281, he was preparing to make a pilgrimage to Santiago de Compostela. In May 1286, he accompanied Edward I to France. On 28 June 1293, he was appointed Constable of Castell y Bere in Merionethshire, and in July of that year, of Hadleigh Castle in Essex. In August 1294, he was preparing to go to Gascony on the King's service, and was in Gascony in 1296-97. On 22 July 1298, he fought at the Battle of Falkirk. In 1298, he was granted a weekly fair and market at his manor in Roydon, Essex, and on 12 April 1299, was appointed Captain and Keeper of the Peace in that county. In 1300, he was at the siege of Caerlaverock Castle, and in 1303 and 1306, saw service in Scotland. He was summoned to military service, to the coronation of Edward II, to various councils, and to Parliament by writs directed Roberto filio Walteri, 'whereby he is held to have become Lord FitzWalter'. On 12 February 1301 he was among the barons who signed a letter intended to be sent to Pope Boniface VIII, repudiating his claim of feudal overlordship of Scotland. On 9 October 1306, he was pardoned of all debts owed to the King. In April 1310, he and his third wife, Alice, intended a pilgrimage to Jerusalem. In February 1317, he was again preparing for a pilgrimage,, and, in November of that year, was granted custody of the town of Colchester, Essex. In June 1320, he was preparing to travel beyond the seas with Edward II. On 6 August 1320, he was exempted from future military service. On 17 January 1326, immediately prior to his death, he had licence to enfeoff his son, Robert, with two manors. He died 19 January 1326, and was succeeded in the barony by Sir Robert FitzWalter, his son by his second marriage, his son Walter FitzRobert by his first marriage having predeceased him in 1293.
Walter FitzRobert, son and heir apparent, who married, in 1286, Joan d'Engaine , daughter of Sir John d'Engaine of Colne Engaine, Essex, by whom he had a son, Robert, who died young, predeceasing him. He died without issue in 1293 at Dunmow Priory, and was buried there. His widow married, in or before 1296, Adam de Welles, 1st Baron Welles, by whom she had three sons, Robert de Welles, 2nd Baron Welles, Adam de Welles, 3rd Baron Welles, and Sir John de Welles, and three daughters, Margaret and Cecily, both of whom became nuns, and a third daughter who married a husband surnamed Mablethorpe.
Ida Fitzwalter, who married firstly Sir Robert de la Warde, and secondly Hugh de Neville, 1st Baron Neville.
Denise Fitzwalter.
Mary Fitzwalter.
Fitzwalter's second wife, Eleanor, was buried at Dunmow Priory. He married thirdly, after 10 May 1308, Alice de Montfort, widow of Sir Warin de Lisle , and daughter of Sir Peter de Montfort of Beaudesert Castle, Warwickshire, by Maud de la Mare, daughter of Sir Henry de la Mare.
