The Beauforts were the four offspring of John of Gaunt and his mistress (later his wife) Catherine Swynford. They were legitimised after the pair's marriage by an Act of Parliament in 1397. They became a powerful and politically active noble line and were constant supporters of the Lancastrian cause. The more notable of the line are as follows:
- John Beaufort (1373-1410) – eldest son and first to bear the name. He was created 1st marquis of Dorset in 1397, then 2nd earl of Somerset and 1st marquis of Somerset later that year. Although deprived of some of his estates upon the deposition of Richard II by Henry Bollingbroke in 1399, he was to become Chamberlain of England and Captain of Calais under Henry.
- Thomas Beaufort (died 1426) – son of John and Catherine, 1st Earl of Dorset then 2nd duke of Exeter. He fought as a commander for both Henry IV against the Scots and Henry V in France and became one of the infant Henry VI’s protectors.
- Henry Beaufort (1377-1447) - son of John and Catherine, took holy orders. He was Bishop of Lincoln from 1398, chancellor for various periods between 1403 and his death, Bishop of Winchester from 1404 and a cardinal from 1427 until his death. He supported the future Henry V, then worked in his administration before being one of the protectors of the juvenile Henry VI. Outside English affairs, he was one who supported the election of pope Martin V at the Council of Constance, and was a firm and vocal backer of the crusade against the Hussites. He began retiring from public life in the late 1430s. He was buried in Winchester Cathedral.
- Edmund Beaufort (1406-1455) – 3rd earl of Dorset, 5th earl of Somerset, 2nd duke of Somerset, was lieutenant of France in the closing stages of the Hundred Years War and took much of the blame for the defeats. He was protected by Henry VI from the worst of the public outcry but still spent time in the Tower of London during one of Henry’s bouts of madness. He died at St. Albans in the first battle of the Wars of the Roses in 1455.
- Lady Joan Beaufort (died 1445), daughter of John Beaufort, became queen of Scotland. She caught the eye and the love of James I of Scotland near the end of his 18 years of captivity in England, and they were allowed to marry before his return to Scotland in 1424. A poem, “The Kingis Laire”, written by James about his love for this beautiful woman seen walking in the garden below his window, is known today.
- Edmund Beaufort (1438-1471) son of Edmund Beaufort, above, was exiled for supporting the usurped Henry VI after Edward IV took the throne in 1461. He returned to fight for the Lancastrians in 1470/71, was captured by the Yorkists at Tewkesbury, and beheaded.
- Lady Margaret Beaufort (1443-1509) daughter of John, 1st duke of Somerset (not mentioned here) was married to Edmund Tudor, the 15th earl of Richmond in 1455, and bore him a son, the future Henry VII, as a twelve-year-old. Edmund died before Henry was born. Parted from Henry when he was forced into exile after the Lancastrian defeat at Tewkesbury in 1471 until his triumph at Bosworth Field in 1485, she agitated on his behalf, was involved in actions against Richard III and was the main proposer of Henry's union with Margaret of York when he became the likely replacement for Richard. After his accession she retired from public life. A pious and intelligent woman, she founded St. Johns and Christ's colleges at Oxford University.