Background
He married the daughter of Sir Robert Neville (d 1413) of Hornby, Margaret Neville, who bore him one son, Henry Beaufort.
He married the daughter of Sir Robert Neville (d 1413) of Hornby, Margaret Neville, who bore him one son, Henry Beaufort.
He was the third of the four children born to John of Gaunt, Duke of Lancaster, and his mistress Katherine Swynford. However, the child died young. After the accession of his half-brother Henry IV, Beaufort was made a Knight of the Garter.
In the following years he held various military posts: constable of Ludlow (1402), admiral of the fleet for the northern parts (1403), captain of Calais (1407), and admiral of the northern and western seas for life (1408/9).
His most notable action during this decade was commanding the forces against the northern rebellion of 1405. He became Chancellor of England on 31 January 1410, an office he held until 5 January 1412 during a time when King Henry was having trouble with the clergy, and then returned to military matters.
Later in 1412 he was created Earl of Dorset. On the accession of Henry V, Beaufort was appointed Lieutenant of Aquitaine (1413) and then captain of Harfleur (1415).
He spent the next years in Normandy as Lieutenant of Normandy (1416).
He was created Duke of Exeter for life in 1416. Beaufort was back in England in 1417, while the king was in Normandy, but had to deal with problems in Scotland. In 1418 he went back to Normandy with a large force, taking part in the sieges of Evreux, Ivry, and Rouen.
After the fall of Rouen in 1419, he was captain of the city and conquered more of the smaller Norman cities.
Finally, in 1419, he took the great fortress of Chateau-Gaillard, midway between Rouen and Paris, after a six-month siege. During this time, Henry V had a policy of creating Norman titles for his aristocrats, thus Beaufort was created Count of Harcourt in 1418.
In 1420, Beaufort helped negotiate the treaty of Troyes. Beaufort was one of the executors of Henry V"s will, and so returned to England in 1422.
He served on the governing council for the infant king Henry VI, though it is likely he spent some time in France as well.
The character of Exeter in Shakespeare"s play Henry V is based on Beaufort, although Beaufort was not actually created Duke of Exeter until after the Battle of Agincourt. As a legitimated grandson of the sovereign, Beaufort bore the arms of the kingdom, differenced by a bordure gobony azure and ermine.