Mortimer, grandson of Roger Mortimer, 1st Baron Mortimer and Maud de Braose, Baroness Mortimer, was born at Wigmore Castle, Herefordshire, England, the firstborn of Marcher Lord Edmund Mortimer, 2nd Baron Mortimer, and Margaret de Fiennes. He was born on April 25, 1287, the Feast of Saint Mark, a day of bad omen. He shared this birthday with King Edward II, which would be relevant later in life. Edmund Mortimer was a second son, intended for minor orders and a clerical career, but on the sudden death of his elder brother Ralph, Edmund was recalled from Oxford University and installed as heir. According to his biographer Ian Mortimer, Roger was possibly sent as a boy away from home to be fostered in the household of his formidable uncle, Roger Mortimer de Chirk. It was this uncle who had carried the severed head of Llywelyn ap Gruffudd of Wales to King Edward I in 1282.
Roger attended the Coronation of Edward II on 25th February 1308 and carried a table bearing the royal robes in the ceremony's procession.
Like many noble children of his time, Roger was betrothed at a young age, to Joan de Geneville (born 1286), the daughter of Sir Piers de Geneville, of Trim Castle and Ludlow. They were married on 20 September 1301 when he was aged fourteen. Their first child was born in 1302.
Through his marriage, Roger not only acquired numerous possessions in the Welsh Marches, including the important Ludlow Castle, which became the chief stronghold of the Mortimers, but also extensive estates and influence in Ireland. However, Joan de Geneville was not an "heiress" at the time of her marriage. Her grandfather Geoffrey de Geneville, at the age of eighty in 1308, conveyed most, but not all, of his Irish lordships to Roger Mortimer, and then retired: he finally died in 1314, with Joan succeeding as suo jure 2nd Baroness Geneville. During his lifetime Geoffrey also conveyed much of the remainder of his legacy, such as Kenlys, to his younger son Simon de Geneville, who had meanwhile become Baron of Culmullin through marriage to Joanna FitzLeon. Roger Mortimer therefore succeeded to the eastern part of the Lordship of Meath, centred on Trim and its stronghold of Trim Castle. He did not succeed, however, to the Lordship of Fingal.
Roger Mortimer's childhood came to an abrupt end when his father was mortally wounded in a skirmish near Builth in July 1304. Since Roger was underage at the death of his father, he was placed by King Edward I under the guardianship of Piers Gaveston, 1st Earl of Cornwall. However, on 22 May 1306, in a lavish ceremony in Westminster Abbey with two hundred and fifty-nine others, he was knighted by Edward and granted livery of his full inheritance.
His adult life began in earnest in 1308, when he went to Ireland in person to enforce his authority. This brought him into conflict with the de Lacys, who turned for support to Edward Bruce, brother of Robert Bruce, King of Scots. Mortimer was appointed Lord Lieutenant of Ireland by Edward II on 23 November 1316. Shortly afterwards, at the head of a large army, he drove Bruce to Carrickfergus and the de Lacys into Connaught, wreaking vengeance on their adherents whenever they were to be found. He returned to England and Wales in 1318 and was then occupied for some years with baronial disputes on the Welsh border.
Mortimer became disaffected with his king and joined the growing opposition to Edward II and the Despensers. After the younger Despenser was granted lands belonging to him, he and the Marchers began conducting devastating raids against Despenser property in Wales. He supported Humphrey de Bohun, 4th Earl of Hereford, in refusing to obey the king's summons to appear before him in 1321 as long as "the younger Despencer was in the King's train." Mortimer led a march against London, his men wearing the Mortimer uniform which was green with a yellow sleeve. He was prevented from entering the capital, although his forces put it under siege. These acts of insurrection compelled the Lords Ordainers led by Thomas, 2nd Earl of Lancaster, to order the king to banish the Despensers in August. When the king led a successful expedition in October against Margaret de Clare, Baroness Badlesmere, after she had refused Queen Isabella admittance to Leeds Castle, he used his victory and new popularity among the moderate lords and the people to summon the Despensers back to England. Mortimer, in company with other Marcher Lords, led a rebellion against Edward, which is known as the Despenser War.
In January 1322 Roger attacked and burnt Bridgnorth but, being heavily outnumbered, was forced to surrender to the king at Shrewsbury. Mortimer joined Lancaster at the Battle of Boroughbridge in May 1322 and warrants for his arrest were issued in July. A death sentence was passed upon Roger but this was commuted to life imprisonment and he was consigned to the Tower of London. In August 1323 Mortimer, aided by the Constable, Stephen de Segrave, drugged the warders and escaped. He attempted to capture Windsor and Wallingford Castles to free imprisoned Contrariants. Roger eventually fled to France, pursued by warrants for his capture dead or alive.
In the following year Queen Isabella, anxious to escape from her husband, obtained his consent to her going to France to use her influence with her brother, King Charles IV, in favour of peace. At the French court the queen found Roger Mortimer, who became her lover soon afterwards. At his instigation, she refused to return to England so long as the Despensers retained power as the king's favourites.
Historians have speculated as to the date at which Mortimer and Isabella actually became lovers. The modern view is that it began while both were still in England, and that after a disagreement, Isabella abandoned Roger to his fate in the Tower. His subsequent escape became one of medieval England's most colourful episodes. However almost certainly Isabella risked everything by chancing Mortimer's companionship and emotional support when they first met again at Paris four years later (Christmas 1325). King Charles IV's protection of Isabella at the French court from Despenser's would-be assassins played a large part in developing the relationship. In 1326, Mortimer moved as Prince Edward's guardian to Hainault, but only after a furious dispute with the queen, demanding she remain in France. Isabella retired to raise troops in her County of Ponthieu; Mortimer arranged the invasion fleet supplied by the Hainaulters and an army supplied by his supporters back in England, who had been sending him aid and advice since at least March 1326.
The scandal of Isabella's relations with Mortimer compelled them both to withdraw from the French court to Flanders, where they obtained assistance for an invasion of England from Count William of Hainaut, although Isabella did not arrive from Ponthieu until the fleet was due to sail. Landing in the River Orwell on 24 September 1326, they were accompanied by Prince Edward and Henry, Earl of Lancaster. London rose in support of the queen, and Edward took flight to the west, pursued by Mortimer and Isabella. After wandering helplessly for some weeks in Wales, the king was taken prisoner on 16 November, and was compelled to abdicate in favour of his son. Though the latter was crowned as Edward III of England on 25 January 1327, the country was ruled by Mortimer and Isabella. On September 21 that same year, Edward II died in captivity. The suspicious death of Edward II has been the subject of many conspiracy theories, including that Mortimer killed him, but none have been proven.
Following the removal of the Despensers, Roger set to work in restoring the status of his supporters, primarily in the Marches, and hundreds of pardons and restorations of property were made in the first year of the new king's reign. Rich estates and offices of profit and power were heaped on Mortimer. He was made constable of Wallingford Castle and in September 1328 he was created Earl of March. However, although in military terms he was far more competent than the Despensers, his ambition was troubling to all. His own son Geoffrey, the only one to survive into old age, mocked him as "the king of folly." During his short time as ruler of England he took over the lordships of Denbigh, Oswestry, and Clun (the first of which belonged to Despenser, the latter two had been the Earl of Arundel's). He was also granted the marcher lordship of Montgomery by the queen.
The jealousy and anger of many nobles were aroused by Mortimer's use of power. Henry, Earl of Lancaster, one of the principals behind Edward II's deposition, tried to overthrow Mortimer, but the action was ineffective as the young king passively stood by. Then, in March 1330, Mortimer ordered the execution of Edmund, Earl of Kent, the half-brother of Edward II. After this execution Henry Lancaster prevailed upon the young king, Edward III, to assert his independence. In October 1330, a Parliament was summoned to Nottingham, just days before Edward's eighteenth birthday, and Mortimer and Isabella were seized by Edward and his companions from inside Nottingham Castle. In spite of Isabella's entreaty to her son, "Fair son, have pity on the gentle Mortimer," Mortimer was conveyed to the Tower. Accused of assuming royal power and of various other high misdemeanours, he was condemned without trial and ignominiously hanged at Tyburn on 29 November 1330, his vast estates forfeited to the crown. His body hung at the gallows for two days and nights in full view of the populace. Mortimer's widow Joan received a pardon in 1336 and survived till 1356. She was buried beside Mortimer at Wigmore, but the site was later destroyed.
In 2002, the actor John Challis, the owner of the remaining buildings of Wigmore Abbey, invited the BBC programme House Detectives at Large to investigate his property. During the investigation, a document was discovered in which Mortimer's widow Joan petitioned Edward III for the return of her husband's body so she could bury it at Wigmore Abbey. Mortimer's lover Isabella had buried his body at Greyfriars in Coventry following his hanging. Edward III replied, "Let his body rest in peace." The king later relented, and Mortimer's body was transferred to Wigmore Abbey, where Joan was later buried beside him.
The marriages of Mortimer's children (three sons and eight daughters) cemented Mortimer's strengths in the West.Sir Edmund Mortimer knt (1302–1331), married Elizabeth de Badlesmere; they produced Roger Mortimer, 2nd Earl of March, who was restored to his grandfather's title.
Margaret Mortimer (1304 – 5 May 1337), married Thomas de Berkeley, 3rd Baron Berkeley
Maud Mortimer (1307 – aft. 1345), married John de Charlton, Lord of Powys
Geoffrey Mortimer (1309–1372/6)
John Mortimer (1310–1328)
Joan Mortimer (c. 1312–1337/51), married James Audley, 2nd Baron Audley
Isabella Mortimer (c. 1313 – aft. 1327)
Katherine Mortimer (c. 1314–1369), married Thomas de Beauchamp, 11th Earl of Warwick
Agnes Mortimer (c. 1317–1368), married Laurence Hastings, 1st Earl of Pembroke
Beatrice Mortimer (d. 16 October 1383), who married firstly, Edward of Norfolk (d. before 9 August 1334), son and heir apparent of Thomas of Brotherton, by whom she had no issue, and secondly, before 13 September 1337, Thomas de Brewes (d. 9 or 16 June 1361), by whom she had three sons and three daughters.
Blanche Mortimer (c. 1321–1347), married Peter de Grandison, 2nd Baron Grandison
Through his son Sir Edmund Mortimer, he is an ancestor of the last Plantagenet monarchs of England from King Edward IV to Richard III. By Edward IV's daughter, Elizabeth of York, the Earl of March is an ancestor to King Henry VIII and to all subsequent monarchs of the United Kingdom.
Mortimer appears in Christopher Marlowe's play Edward II (c. 1592) as well as Bertolt Brecht's The Life of Edward II of England (1923). In Derek Jarman's film Edward II (1991), based on Marlowe's play, he is portrayed by Nigel Terry.
Mortimer is also a character in Les Rois maudits (The Accursed Kings), a series of French historical novels by Maurice Druon. He was portrayed by Claude Giraud in the 1972 French miniseries adaptation of the series, and by Bruno Todeschini in the 2005 adaptation.
Mortimer is a character in World Without End and is played by Hannes Jaenicke.