he returned with Henry from a mission to France (Cont. Gerv. Cant. ii. 219). About Whitsuntide he supported Montfort at a council held ‘rege et concilio suo ignorantibus’ (Dunstable Annals, p. 222, but cf. Bémont, p. 199). He joined the baronial army and took part in the attack on Peter of Aigueblanche [q. v.], bishop of Hereford (Dunstable Annals, pp. 221–2). On 7 Aug. he was made constable of Pevensey Castle, and on 23 Aug. joint commissioner to treat with the Welsh (Fœdera, i. 430).
By the autumn Warenne again wavered. After the flight of Edward from the capital the Londoners turned Warenne out of the city (Dunstable Annals, p. 225), whereupon he and Henry of Cornwall led a great secession to the royalists. Edward's timely grants of land encouraged the seceders. Warenne was with the king when, on 3 Dec., he was refused admission to Dover Castle (Cont. Gerv. Cant. ii. 229). On 16 Dec. he signed the agreement to submit to the arbitration of St. Louis (Royal Letters, ii. 252). On 24 Dec. the king made him guardian of the peace in Surrey and Sussex.
Warenne fought strenuously on the king's side in the war that followed the repudiation of the Mise of Amiens. In March 1264 he was with the king at Oxford, whence he went with Roger de Leybourne [q. v.] to protect his castle of Reigate from the Londoners (Rishanger, De Bello, p. 22). He soon retreated to Rochester, where he arrived on 16 April. On the 19th Leicester took the outworks of the castle and drove Warenne into the Norman keep, where he held out until 26 April, when Leicester retreated to London on the approach of Edward (Hemingburgh i. 313; Wykes, pp. 146–7; Cont. Gerv. Cant. ii. 235–6). On 29 April Warenne left Rochester. A few days later he was at his castle of Lewes, where he entertained Edward on the night of 13 May (Battle Chronicle apud Bémont, p. 376). In the battle of Lewes, 14 May, Warenne fought on the right or north wing of the royalist host commanded by Edward (Rishanger, p. 26, Rolls Ser.; Hemingburgh, i. 316). If, however, he accompanied Edward's pursuit of the Londoners, he soon returned to the town, where, after the capture of the king, he fought a fierce fight in the streets with the victorious barons (Battle Chronicle, u.s. p. 377). Beaten signally in this, he rode off with Hugh Bigod and his Lusignan brothers-in-law over the Ouse bridge to Pevensey Castle, of which he was still constable. Leaving behind a garrison, they thence fled to the exiled queen in France. Warenne's flight was severely denounced by the chroniclers. Wykes (p. 151), the royalist, makes it an excuse for Edward's surrender.
On 18 June all Warenne's lands, save Lewes and Reigate, were handed over to Earl Gilbert of Gloucester. He remained abroad for nearly a year, staying partly in France and partly in Flanders. The quarrel of Leicester with Gloucester at last gave him his opportunity. On 19 March 1265 he was summoned to appear in parliament ‘to do and suffer justice.’ Early in May, along with William de Valence, he landed in Pembrokeshire (Wykes, p. 165; Royal Letters, ii. 282). They joined the escaped Edward and Gloucester at Ludlow, and took part in the Evesham campaign. On the night of 1–2 Aug. Warenne accompanied Edward in his secret march on Kenilworth, and took part in its capture on the morning of the latter day (Liber de Ant. Leg. pp. 74–5). After Evesham he reduced Kent and the Cinque ports (Royal Letters, ii. 289). On 27 May 1266 he and William of Valence suddenly attacked Bury St. Edmund's. The abbey at once yielded, and the townsfolk atoned for their disloyalty by a fine (Cont. Flor. Wig. ii. 197). In 1267, still acting with William of Valence, he mediated between Gloucester and the king and his son (Rishanger, p. 50, Rolls Ser., and De Bello, p. 60; Cont. Gerv. Cant. ii. 246). At the conclusion of the disturbances Warenne obtained a formal pardon for his rebellions against the king (Abbreviatio Placitorum, p. 168), and for the excesses of himself and his followers up to 1268 (cf. Cal. Patent Rolls, 1281–92, p. 167). On 24 June 1268 he took the cross at the same time as Edward (Wykes, p. 218). This did not prevent fierce quarrels with rival barons. In 1269 a contest broke out between Warenne and Henry de Lacy [q. v.], the young earl of Lincoln, with regard to their rights over a certain pasture. Both earls prepared to wage private war, but the king forced them to refer the dispute to the justices, who decided in favour of Lacy (Flores Hist. iii. 17–18). On 13 Oct. 1269 Warenne was present at the translation of Edward the Confessor (Wykes, p. 226). A dispute broke out between Warenne and Alan de la Zouch about a certain manor. On 19 June 1270 the case was being tried in Westminster Hall (ib. p. 234). Fearing lest once more the law might be adverse, Warenne overwhelmed Alan and his eldest son with reproaches. Thereupon his followers set upon the Zouches, dangerously wounding the father. The son only escaped by flight. The king and his son were in the neighbouring palace, and were
