Philip of Charolais at Saint-Omer, and was surrendered on 13 Oct. after Burgundy's return. He then accompanied Sigismund on his coasting voyage from Calais to Dordrecht, where he was dismissed with presents (Walsingham, Ypodigma Neustriæ, p. 471; Capgrave, Chron. p. 315 ; cf. Aschbach, Kaiser Sigmund).
Gloucester took part in Henry V's second French expedition in 1417. He took Lisieux without difficulty (Redman, p. 51). On 19 Sept. he was commissioned to treat for the surrender of Bayeux (Fœdera, ix. 493). After Easter 1418 he overran the Cotentin, finding serious resistance at Cherbourg, which only surrendered on 1 Oct. after a long siege (T. Livius Foro-Juliensis, pp. 51-6 : Gregory, Chronicle, p. 121). He then joined Henry V at the siege of Rouen, where he took up quarters with the king at the Porte Saint-Hilaire (Paston Letters, i. 10; Collections of London Citizen, Camd. Soc., pp. 11, 16, 23, 25). In January 1419 he was made governor of the captured capital of Normandy (Monstrelet, iii. 308). In April 1419 he had license to treat for a marriage between himself and Blanche of Sicily, daughter of Charles, king of Navarre (Fœdera, ix. 493). Nothing further came of this. He was present at the first interview of Henry V and the French court at Meulan, and on 1 June was a commissioner to treat for peace and for Henry's marriage (Fœdera, ix. 761). lieutenant of England (Fœdera, ix. 830). In February 1421 his commission was concluded by the king's return. In the summer of 1421 Gloucester again accompanied Henry V to France. He afterwards returned to England, and replaced Bedford as regent when the latter accompanied Queen Catherine to Paris in May 1422.
Gloucester was still in England when Henry V died on 31 Aug. 1422, leaving an infant heir. On his deathbed Henry warned Gloucester not to selfishly prefer his personal interests to those of the nation (Waurin, Chron. 1399-1422,p. 423). The dying king appointed him deputy for Bedford during the latter's presence in France. Humphrey at once entered into this position. On 28 Sept. he received the seals from the chancellor in the name of his little nephew, Henry VI. But the council exercised the executive power, and he did not venture to gainsay their acts. In the end the question of the regency was referred to parliament, which Gloucester opened on 9 Nov. (Fœdera, x. 257). He claimed the regency, both on grounds of kinship and the will of Henry V. Parliament rejected his pretensions. At last royal letters patent, confirmed by act of parliament, provided that Gloucester, during his brother's presence in England, was only to act as principal counsellor after him, but that when Bedford was absent Gloucester was to be himself protector and defender of the kingdom and church, and chief counsellor to the king. As Bedford was likely to be fully occupied in France, Gloucester at once became protector, with a salary of eight thousand marks a year. The real power, however, remained with the council, of which Gloucester was little more than the chairman, with some small rights of dispensing the minor patronage of the crown. The new council only took office on five stringent conditions which severely limited his power.
Gloucester's first acts fully justified the caution of Henry V and the council. Before June 1421 Jacqueline of Bavaria fled to the English court, where she was given a pension and allowed to act as godmother to Henry VI. Born on 25 July 1401, she was the only daughter of William IV, count of Hainault, Holland, and Zealand, and lord of Friesland, and of Margaret of Burgundy, sister of John the Fearless. Her first husband, who soon died, was the dauphin John, Charles VII's elder brother. On her father's death in 1417 she had succeeded to the sovereignty of his three counties. In 1418 she had married her second husband, John IV, duke of Brabant, her own cousin, and cousin of Philip of Burgundy. But her father's brother, John the Pitiless, at one time bishop of Liège, wrested Holland and Zealand from her by a treaty with her weak husband, 21 April 1420. The Spanish antipope, Benedict XIII, annulled her marriage with Brabant soon after her arrival in England, and, probably in the autumn of 1422, Gloucester married her (by October 1422, Particularités Curieuses, p. 58; before 7 March 1423, Stevenson, i. 211, pref.; Saint-Remy, ii. 82; Æneas Sylvius, Commentarii, pp. 412-15, ed. Rome, 1584). Lydgatewrotea ballad to celebrate the event. On 20 Oct. 1423 she was denizened (Fœdera, x. 311). Gloucester spent Christmas at St. Albans with his wife (cf. Amundesham, i. 7). On 7 Jan. 1424 both were admitted to the fraternity of the abbey, which was afterwards his favourite place of devotion (ib. i. 66).
Gloucester had dealt a death-blow to English interests abroad by a marriage which directly put him in competition with Philip