Edward was knighted at the coronation of his cousin,
King Richard II, on 16 July 1377, and in May 1387 was admitted to the
Order of the Garter. He was close to the King throughout his life, and benefited even in his youth from numerous royal grants and appointments. On 25 February 1390, the King created him
Earl of Rutland, and on 22 March 1391 made him admiral of the northern fleet; he was made sole admiral the following November. In 1392, he became a member of King Richard's council, and was with the King during a campaign in Ireland in 1394–5. Prior to that, although no patent has been found, he was created
Earl of Cork. He used the styles of Rutland and Cork throughout the remainder of his life. In the late 1390s, Edward was sent on embassies to France and to the
Count Palatine and was appointed to numerous offices, including Constable of
Dover Castle,
Lord Warden of the Cinque Ports, Keeper of the
Channel Islands,
Constable of the Tower, Warden of the
New Forest, Keeper of
Carisbrooke Castle and Lord of the
Isle of Wight. On 11 July 1397, Richard II arrested his uncle
Thomas of Woodstock, Duke of Gloucester. Edward was granted Gloucester's office of
Constable of England on 12 July and was one of an eight-member commission that on 5 August determined to accuse Gloucester,
Thomas Beauchamp, Earl of Warwick, and
Richard FitzAlan, Earl of Arundel of high treason. Edward was later accused of having sent his servants to assist in Gloucester's subsequent murder at
Calais, an allegation he denied. However, on 28 September 1397, he received a large grant of Gloucester, Warwick and Arundel's forfeited lands. On 29 September, he was created
Duke of Aumale, a title that had earlier been granted to Gloucester on 3 September 1385. On 16 September 1398 Edward presided as constable over the aborted judicial combat between Henry Bolingbroke, the future
Henry IV and
Thomas de Mowbray, Duke of Norfolk, which ended with Bolingbroke and Norfolk being exiled by King Richard. Additional royal grants followed during the final years of King Richard's reign. On 10 February 1398 Edward was appointed
Warden of the
West March. On 11 August 1398 he was granted custody of the lands of
Roger Mortimer, Earl of March, during Mortimer's
son's minority, and on 20 March 1399 lands which had lately belonged to
John of Gaunt, Duke of Lancaster, and which were part of the inheritance of his son, Henry Bolingbroke, the future
King Henry IV. In May 1399, Edward accompanied King Richard to Ireland, and in the King's absence, Henry Bolingbroke (the future King
Henry IV) landed towards the end of June near
Ravenspur,
Yorkshire, with a small band of exiles. During the following three weeks, Bolingbroke's forces were augmented by loyal Lancastrian supporters and were soon joined by the most powerful of the northern magnates,
Henry Percy, Earl of Northumberland and
Ralph Neville, Earl of Westmorland. King Richard's fatal decision to divide his army while still in Ireland has been attributed to advice from Edward. The King sent some of his troops ahead to North Wales under the command of the
John Montacute, Earl of Salisbury, and about 19 July arrived at
Milford Haven in South Wales with the rest of his forces. News of the strength of Bolingbroke's army then caused the King to desert the troops with him and travel to North Wales in an attempt to join Salisbury. However Salisbury's troops, having heard rumours of the King's death, had dispersed, and the army left behind by the King did so as well. Although he could have made his escape by sea, the King ensnared himself in negotiations with Bolingbroke. Meanwhile, Edward's father
Edmund of Langley, 1st Duke of York, who had been left in charge of the kingdom during King Richard's absence, and had raised an army on hearing of Bolingbroke's landing in Yorkshire, capitulated to Bolingbroke at
Berkeley on 27 July. Edward speedily deserted to Bolingbroke as well and was reportedly wearing Bolingbroke's
livery when he was among those sent by Bolingbroke to the King at
Flint Castle. ==Reign of Henry IV==