Humfrey joined his older brother on campaigns in France from 1415 almost until the latter’s death in 1422. Henry V’s will placed Humfrey in charge of his baby son’s upbringing and as a senior member of the Royal Council which would govern England until the young king came of age.
Unfortunately, Humfrey felt he should have been given even more authority and this led to many years of friction with the Council and especially with its dominant member Cardinal Beaufort. Henry V had named his brother, John duke of Bedford, as Regent of France, but Humfrey had his own policies on continental wars which ran contrary to those of Bedford and Beaufort. He led an unsuccessful invasion of Hainaut in an attempt to re-assert control over his wife’s lands, from her former husband, but chose to abandon her there after being challenged to fight a duel.
He replaced her with his mistress Eleanor Cobham. When Bedford died (1435) Humfrey became heir apparent to the English throne, since the adolescent Henry VI had not yet married. A huge row developed between Humfrey and Beaufort over the latter’s attempt to move his personal fortune out of England. Some years later Eleanor, duchess of Gloucester was put on trial for witchcraft – a very serious offence in the Middle Ages. Her imprisonment for life and compulsory divorce left Humfrey more politically isolated but he continued to speak out against government policies, especially the peace treaty around the king’s marriage to Margaret of Anjou.
He was summoned to Parliament in 1447 by the now adult and married king to account for his behaviour and arrested for treason. He died a few days later. Rumours began that he had been murdered. He gained a reputation as ‘Good duke Humfrey’ amongst the populace and his alleged murderers became victims of the Cade Rebellion of 1450. Richard duke of York made political capital out of this and took on the mantle of Humfrey when he opposed the duke of Somerset in the following five years until the first battle of St Albans. Humfrey was a collector of books and this is commemorated by the oldest part of the Bodleian Library at Oxford now known as Duke Humfrey’s Library.