Before 1312 or perhaps 1322 (depending on whether you count Piers Gaveston as earl of Cornwall at the time of his death; otherwise, the earl of Lancaster was the first), no English earl had been executed since Waltheof in 1076, although Edward I executed the Scottish earl of Atholl, John de Strathbogie, in November 1306. Edward II's turbulent reign and its aftermath - the period from 1327 to 1330 before Edward III took over the governance of his realm really belongs politically to Edward II's reign rather than his son's - saw the executions of no fewer than seven earls (Cornwall, Lancaster, Carlisle, Arundel, Winchester, Kent and March), with two more (Gloucester and Hereford) killed in battle. In no particular order, here are some notes on the English earls of the early fourteenth century and their deaths.
Thomas, earl of Lancaster, Leicester and Derby (and also of Lincoln and Salisbury in 1311 on the death of his father-in-law), c. 1278 - 22 March 1322
Thomas succeeded his father, Edward I's brother Edmund (d. 5 June 1296), in 1298, even though he was still under twenty-one. He was beheaded at Pontefract on 22 March 1322, having committed treason by inviting Robert Bruce's army to England to help him and his allies fight against Edward II, though contemporary chroniclers were in little doubt that his real crime in Edward's eyes was his killing of Piers Gaveston just under ten years earlier.
Henry de Lacy, earl of Lincoln and Salisbury (c. 1250 - shortly before 15 February 1311)
Henry died a natural death, aged about sixty. His only surviving legitimate child was his daughter Alice, and his lands and titles passed to his son-in-law Thomas of Lancaster, above.
Piers Gaveston, earl of Cornwall (c. 1270s/early 1280s - 19 June 1312)
Created earl of Cornwall on 6 August 1307 by an infatuated Edward II. Probably the only man exiled from England no fewer than three times, and beheaded at Blacklow Hill, Warwickshire in the presence of the earls of Lancaster, Hereford and Arundel, having been taken prisoner by the earl of Warwick.
Gilbert de Clare, earl of Gloucester and Hertford (c. 10 May 1291 - 24 June 1314)
Edward I's eldest grandchild, Gilbert was killed at the battle of Bannockburn, aged twenty-three. Gilbert's early death was profoundly significant: firstly it removed a moderate influence who was close to Edward II, his uncle, and who was also trusted and respected by the other magnates; secondly, his vast fortune passed to his three sisters and their husbands, and made the men powerful and influential. Without Gilbert's death, Hugh Despenser the Younger could never have become the force he was in the 1320s.
Guy Beauchamp, earl of Warwick (c. 1272 - 12 August 1315)
One of the few English earls of the era not closely related to Edward II by blood or marriage. Guy died of natural causes in his early or mid-forties. Much later rumours had it that he had been poisoned by Edward II or friends of the king in revenge for his role in Piers Gaveston's death, which is vanishingly unlikely.
Thomas of Brotherton, earl of Norfolk (1 June 1300 - 4 August 1338)
Edward II's half-brother. Created earl of Norfolk at the age of twelve in December 1312, a few weeks after the birth of his nephew Edward of Windsor displaced him as heir to the throne. Thomas died of natural causes.
Edmund of Woodstock, earl of Kent (5 August 1301 - 19 March 1330)
Edward II's half-brother. Created earl of Kent in July 1321, aged not quite twenty. Edmund was beheaded in March 1330, still only twenty-eight, on the orders of Isabella of France and Roger Mortimer, for attempting to free Edward of Caernarfon from Corfe Castle.
Andrew Harclay, earl of Carlisle (c. 1270 - 3 March 1323)
Sheriff of Cumberland from 1311 and completely loyal for many years to Edward II, who rewarded him for his victory over the earls of Lancaster and Hereford at Boroughbridge in March 1322 with the earldom of Carlisle. Andrew held the title for less than a year, being hanged, drawn and quartered in Carlisle for treason (he had negotiated a peace treaty with Robert Bruce without Edward's permission or knowledge).
John de Warenne, earl of Surrey and Sussex (30 June 1286 - 29/30 June 1347)
Edward II's nephew by marriage. John succeeded his grandfather John de Warenne (d. 1304) when he turned twenty-one in 1307. He died of natural causes in his early sixties.
Edmund Fitzalan, earl of Arundel (1 May 1285 - 17 November 1326)
Brother-in-law of the earl of Surrey, but not closely related to the king (he and Edward II were only third cousins or thereabouts). Edmund's career followed an interesting trajectory: present at the death of Piers Gaveston in June 1312, he later became a loyal ally of Edward II, and was beheaded without trial by Roger Mortimer and Isabella of France in Hereford a few weeks after their invasion.
Humphrey de Bohun, earl of Hereford and Essex (c. 1276 - 16 March 1322)
Married Edward I's daughter Elizabeth in 1302, and was killed horribly at the battle of Boroughbridge on 16 March 1322, during the Contrariant rebellion against his brother-in-law Edward II.
Aymer de Valence, earl of Pembroke (c. 1275 -23 June 1324)
Son of Henry III's half-brother William de Valence, and earl of Pembroke on the death of his mother in 1307. Aymer died of natural causes in France on his way to Paris to meet Charles IV; the Brut chronicler, who disliked him for his role in the execution of the earl of Lancaster, claimed maliciously that he died on the privy. In fact he was taken ill at dinner, collapsed and died suddenly in a servant's arms before he could be shriven.
Hugh Despenser the Elder, earl of Winchester (1 March 1261 - 27 October 1326)
Father of Edward II's notorious 'favourite', and created earl of Winchester in 1322. Hugh was hanged in his armour by Roger Mortimer and Isabella of France, and his body fed to dogs. He was sixty-five.
Robert de Vere, earl of Oxford (24 June 1257 - 19 April 1331)
A remarkably obscure and insignificant earl who played no role at all in Edward II's reign, except that he seems to have supported the king during the crisis of 1308 and was present at the publication of the Ordinances in September 1311. Staying out of politics served Robert well: he died of natural causes in his seventies, and was succeeded by his nephew John, his son Thomas having died in 1329.
John of Brittany, earl of Richmond (1266 - 17 January 1334)
Son of Edward I's sister Beatrice and thus Edward II's first cousin, and brother of Duke Arthur II of Brittany, though he spent most of his life in England. John was loyal to Edward until at least late 1325, then joined Mortimer and Isabella. Oddly, he never married, and died of natural causes in his late sixties.
Edward (III) of Windsor, earl of Chester (13 November 1312 - 21 June 1377)
Created earl of Chester by his doting father the king when he was only eleven days old, Edward acceded to the throne in January 1327 and died of natural causes in his sixties.
John of Eltham, earl of Cornwall (15 August 1316 - 13 September 1336)
Second son of Edward II and Isabella of France, and created earl of Cornwall in 1328, near the start of his brother's reign - not by his father, interestingly enough, though the earldom of Cornwall lay vacant for many years after Piers Gaveston's death - it's as though Edward II didn't want anyone else to hold the title, even his own son. John died a natural death at the age of only twenty; the story told by a Scottish chronicler that John was killed by his brother the king can safely be dismissed.
Roger Mortimer, earl of March (25 April 1287 - 29 November 1330)
The queen's favourite who created himself earl of March in 1328; executed by Edward III on fourteen charges of treason and usurping royal power a few weeks after the young king took over the governance of his realm.