Thomas of Lancaster, Duke of Clarence

Thomas was born before 25 November 1387 as on that date his father's accounts note a payment made to a woman described as his nurse.^[3] 29 September 1388^[4] sometimes features as his birth date, but it now seems clear that Thomas was born before Christmas 1387.^[5] He was probably born in London,^[3] but some sources give Kenilworth Castle.^[6]

In November or December 1411, Thomas married Margaret Holland, widow of his uncle John Beaufort, 1st Earl of Somerset, and daughter of Thomas Holland, 2nd Earl of Kent. No children were born from this union, although Thomas was stepfather to her six children from her first marriage, who were his first cousins. He had, however, a natural son, Sir John Clarence,^[7] called "Bastard of Clarence" who fought by his father's side in France.

After Thomas's father became ill in 1411, his older brother became head of the royal council. Conflicts arose between the young Henry and his father when the prince gathered a group of supporters favouring his policy of declaring war on France. The prince was removed from the council by his father after he had defied the king's wishes by persuading it to declare war. Thomas was given his brother's seat, and fell in line with his father's peace policy.^[8] Though he remained Lord Lieutenant of Ireland until 1413, he did not return to Ireland after 1409.^[9] He seems to have been a conscientious Governor there, but was hampered in his efforts to keep the peace by the chronic shortage of money in Ireland.^[10]

During the wars of his elder brother Henry V in France, Clarence fought in both the Siege of Caen and the Siege of Rouen (29 July 1418 – 19 January 1419), where he commanded the besieging force. After Henry had negotiated the Treaty of Troyes, in which he became heir to the French throne, the king returned to England with his new wife Catherine. The Dauphin, the disinherited former heir, refused to accept the situation and organised continuing resistance, aided by a Scottish army led by John Stewart, Earl of Buchan.

Following the king's instructions, Clarence led 4,000 men in raids through Anjou and Maine.^[11] This chevauchée met with little resistance, and by Good Friday, 21 March 1421, the English army had made camp near the little town of Vieil-Baugé. The Franco-Scots army of about 5,000 also arrived in the Vieil-Baugé area to block the English army's progress; it was commanded by the Earl of Buchan and the Marshal of France, the Sieur de Lafayette; however, the English forces were dispersed, and, significantly, many of the English archers had ridden off in search of plunder or forage. On Easter Saturday, one of these foraging groups captured a Scots man-at-arms whom they brought before the Duke of Clarence. Clarence was keen to engage the enemy; however, he had a problem: the following day was Easter Sunday, one of the holiest days in the Christian calendar, when a battle would be unthinkable. A two-day delay was also deemed as out of the question.^[12][13] According to the chronicles of Walter Bower, both commanders agreed a brief truce to celebrate Easter, but then joined battle that day.^[14]

Perhaps underestimating the size of the Franco-Scottish army, Clarence decided to launch a surprise cavalry-led attack rather than use his archers against the enemy. With only about 1,500 men-at-arms available, and virtually no archers, he charged the Franco-Scottish lines. The shock temporarily disordered the Franco-Scots, but soon Clarence and his knights were overwhelmed. Clarence was unhorsed by a Scottish knight, Sir John Carmichael of Douglasdale, and finished off on the ground by Sir Alexander Buchanan, probably with a mace,^[12][15] "his jewelled and crowned helmet wrenched from his head as a prize".^[16]

Clarence's natural son John accompanied the remains of his father from Baugé to Canterbury for their interment. This Sir John Clarence had a grant of lands in Ireland from Henry V and was buried in Canterbury Cathedral.

Clarence's executors, as seen in a legal record of 1430, were John Colvylle, of Neuton, Cambridgeshire, knight; Henry Merston, of Westminster, clerk and his widow, Margaret, Duchess of Clarence, living in Bermondsey, Surrey.^[17]

• Duke of Clarence and Earl of Aumale (9 July 1412 – 22 March 1421); extinct upon his death

• Knight, Order of the Bath (12 October 1399 – 22 March 1421)
• Knight, Order of the Garter (1400 – 22 March 1421)

• Lord High Steward of England (1399–1421) — he was the last permanent holder of this office, the highest in medieval England.
• Chief Governor of Ireland (1401–1413)
• Lord High Admiral (1405–1406)
• Lieutenant of Aquitaine (1412–1413)
• Lord High Steward of Chester (1415)
• Constable of the Army (1417)
• Lieutenant-General of the Army in France and Normandy (1417 and 1421)

• Weir, Alison (2002). Britain's Royal Family: A Complete Genealogy. The Bodley Head London, UK. ISBN 0-7126-4286-2. pages 102 & 123
• Cokayne, G.; Gibbs, V.; Doubleday, H.A., eds. (1913). The Complete Peerage. Vol. 3 (2nd ed.). London: St. Catherine Press. pp. 258–9.
• Cokayne, G.E. (2000). The Complete Peerage of England, Scotland, Ireland, Great Britain and the United Kingdom, Extant, Extinct, or Dormant. Alan Sutton. Vol I pg 368
• Harriss, G.L. (2010). "Thomas, duke of Clarence (1387–1421)". Oxford Dictionary of National Biography (online) (online ed.). Oxford University Press. doi:10.1093/ref:odnb/27198. (Subscription or UK public library membership required.)
• Mortimer, Ian (2007). The Fears of Henry IV: The Life of England's Self-Made King. London: Jonathan Cape. ISBN 978-0-224-07300-4.
• Orme, Nicholas (2001). Medieval Children. Yale University Press.
• Otway-Ruthven, A.J. (1993). A History of Medieval Ireland. New York: Barnes and Noble.

• "Thomas Plantagenet, duke of Clarence". Encyclopædia Britannica. 20 July 1998.