Guy de Beauchamp, 10th Earl of Warwick ( 1272 – 12 August 1315) was an English magnate, and one of the principal opponents of King Edward II and his favourite, Piers Gaveston. Guy was the son of William de Beauchamp, the first Beauchamp earl of Warwick, and succeeded his father in 1298. He distinguished himself at the Battle of Falkirk and subsequently, as a capable servant of the crown under King Edward I. After the succession of Edward II in 1307, however, he soon fell out with the new king and the king's favourite, Piers Gaveston. Warwick was one of the main architects behind the Ordinances of 1311, that limited the powers of the king and banished Gaveston into exile.

When Gaveston returned to England in 1312—contrary to the rulings of the Ordinances—he was taken into custody by Aymer de Valence, 2nd Earl of Pembroke. Warwick abducted Gaveston and, together with Thomas, 2nd Earl of Lancaster, had him executed. The act garnered sympathy and support for the king, but Warwick and Lancaster nevertheless managed to negotiate a royal pardon for their actions. After the disastrous defeat at the Battle of Bannockburn in 1314, King Edward's authority was once more weakened, and the rebellious barons took over control of government. For Warwick the triumph was brief; he died the next year.

Guy de Beauchamp, 10th Earl of Warwick

Guy de Beauchamp is today remembered primarily for his part in the killing of Gaveston, but by his contemporaries he was considered a man of exceptionally good judgement and learning. He owned what was for his time a large collection of books, and his advice was often sought by many of the other earls. Next to Lancaster, he was the wealthiest peer in the nation, and after his death his lands and title were inherited by his son, Thomas de Beauchamp, 11th Earl of Warwick.

Guy de Beauchamp, 10th Earl of Warwick

Family background

Guy de Beauchamp was the first son and heir of William de Beauchamp, 9th Earl of Warwick (c. 1238 – 1298). His mother was Maud FitzJohn, daughter of John Fitzgeoffrey, who was Justiciar of Ireland and a member of the council of fifteen that imposed the Provisions of Oxford on King Henry III. William was the nephew of William Maudit, 8th Earl of Warwick, and when his uncle died without issue in 1268, he became the first Beauchamp earl of Warwick. In 1271 or 1272 his first son was born, and in reference to the new family title, William named his son after the legendary hero Guy of Warwick. William de Beauchamp was a capable military commander, who played an important part in the Welsh and Scottish wars of King Edward I.

Guy de Beauchamp, 10th Earl of Warwick

A marriage between Guy and Isabel de Clare, daughter of Gilbert de Clare, 6th Earl of Hertford, was contemplated, or possibly even took place and then annulled. It was not until early 1309 that Guy married Alice de Toeni, a wealthy Hertfordshire heiress. By this time Guy had already succeeded as Earl of Warwick, after his father's death in 1298.

By his wife, Alice, Guy had two daughters and two sons—Thomas, his heir and successor, and John de Beauchamp, Lord Beauchamp KG (1315 – 2 December 1360), who carried the royal standard at the Battle of Crécy. Maud de Beauchamp (died 1366), married before Easter term 1332 Geoffrey de Say, 2nd Lord Say, by whom she had issue. The Barons Saye and Sele are their descendants. Elizabeth de Beauchamp (c. 1316 – 1359), married before Easter term 1332 Thomas Astley, 3rd Lord Astley, by whom she had two sons, William Astley, 4th Lord Astley and Sir Thomas Astley, ancestor of the Astleys of Patshull and of Everley.

By an unknown mistress (or mistresses), Earl Guy also had three daughters: Isabel de Beauchamp; married John de Clinton. Emma de Beauchamp; married Roland de Oddingseles. Lucia de Beauchamp (also known as Lucy); married Robert de Napton, Knt., the son of Sir Adam Napton. Lucia and Sir Robert had a son Adam Napton, who married Margaret Helier.