Who Was Thomas Of Lancaster, 1st Duke Of Clarence?

When we think of members of the monarchy, we often focus on Elizabethan, Victorian, Tudor, and Edwardian times. While these periods in time have all proved incredibly interesting, we often overlook Medieval times, and that is such a shame.

During Medieval times, we saw some prominent figures rise, including Thomas of Lancaster, 1st Duke of Clarence.

A skilled and fearsome soldier, the son of Henry IV of England, the brother of Henry V, Thomas of Lancaster, 1st Duke of Clarence was heir to the throne in the event of his brother’s death.

Here’s a look at the life and times of Thomas of Lancaster, 1st Duke of Clarence.

Who Was Thomas Of Lancaster, 1st Duke Of Clarence?
Image: James William Edmund Doyle, CC0, via Wikimedia Commons.

Early Life

Believed to have been born on the 29th of September, 1388, or more likely before Christmas, 1387, there is some uncertainty regarding his origins and his birth.

Some believe that he was born in London, whereas other sources point to the fact that he may have been born at Kenilworth Castle.

Records are hazy regarding his upbringing, so not a great deal is known as Thomas when he was a child and young man growing up.

Who Was Thomas Of Lancaster, 1st Duke Of Clarence?
Image: Sodacan, CC BY-SA 3.0 https://creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons


In 1411, between November and December, Thomas married Margaret Holland, who was the widow of his uncle, the 1st Earl of Somerset, John Beaufort.

The couple had no children, although Thomas became stepfather to her six children from her previous marriage, who was actually his first cousins.

Thomas already had a natural son, who was Sir John Clarence, known as the ‘Bastard of Clarence’ who would go on to fight side by side with his father in France.

Life As A Soldier

Thomas would go on to fight at both the Siege of Rouen and the Siege of Caen during the wars of his brother, Henry V.

Thomas would take charge of the army and would lead 4,000 men on raids across Maine and Anjou. The English army faced very little opposition, though, before the Battle of Agincourt, Thomas would become injured and be forced to return to England to recover.

Once recovered, he would return to France and take charge of his army once more.

After Henry V returned to England in 1421, this left Thomas in France as a distinguished soldier and lieutenant.

Who Was Thomas Of Lancaster, 1st Duke Of Clarence?
Image: Bibliothèque nationale de France, Public domain, via Wikimedia Commons.

On the 21st of March, 1421, Clarence’s army, made up of close to 3,000 soldiers, was resting near the town of Bauge. A much larger army of Franco-Scots engaged the English forces and took them by surprise and quickly got the upper hand.

Clarence decided to launch a counterattack right away as the following day was Easter Sunday, which was one of the holiest days in the Christian calendar, and subsequently, no battles could be fought on that day.

Clarence underestimated the size of his opponent’s army and rushed into battle without a clear strategy and rushed the opposition.

Without anywhere near enough archers, Clarence’s army was quickly dispatched by the Franco-Scots, and Clarence and his Knights were defeated.


Thomas of Lancaster, 1st Duke of Clarence died in battle when he was unhorsed by a Scottish Knight named Sir John Carmichael.

A knight known as Sir Alexander Buchanan dispatched Clarence while he was on the ground, finishing him off with a mace. He died in battle aged just 33. His remains, accompanied by his son, were returned to England and were buried at Canterbury Cathedral.