Roger Mortimer (11 April, 1374 – 20 July, 1398), was 4th Earl of March and 6th (??) Earl of Ulster. Between 1385 and 1398 he was heir presumptive to Richard II of England.
Family
His father was the powerful Edmund Mortimer, 3rd Earl of March, and his mother was Philippa, Countess of Ulster and March, the only issue of Lionel of Antwerp, Duke of Clarence, a son of King Edward III of England and Philippa of Hainault. As the senior descendent of this line through Edward III's second surviving son, Roger Mortimer was named by the childless King Richard II of England as his heir presumptive.
He was the father of Anne Mortimer and Edmund Mortimer, 5th Earl of March.
Family wealth
He held enormous estates in Wales, and succeeded to the titles and estates of his family when a child of seven. One month later he was appointed Lord Lieutenant of Ireland, and his uncle Sir Thomas Mortimer acted as his deputy. Being a ward of the Crown, his guardian was Thomas Holland, 2nd Earl of Kent, half-brother to Richard II.
The importance which he owed to his hereditary influence and possessions, and especially to his descent from Edward III, was immensely increased when Richard II publicly acknowledged him as heir presumptive to the crown in 1385. In 1388, Mortimer married Eleanor Holland , daughter of the Earl of Kent.
Conflict in Ireland
In 1394 he accompanied Richard II to Ireland, but notwithstanding a commission from the king as lieutenant of the districts over which he exercised nominal authority by hereditary right, he made little headway against the native Irish chieftains.
March enjoyed great popularity in England though he took no active part in opposing the despotic measures of the King; in Ireland he illegally assumed the native Irish costume. In August 1398 he was killed at the Battle of Kells in a fight with an Irish clan, and was buried in Wigmore Abbey.
His titles and the designation of heir presumptive passed to his young son, Edmund Mortimer, 5th Earl of March.