Issue of Edward III of England – 3 February 1399), 1st Duke of Lancaster, fourth son. From the marriage of John of Gaunt and Blanche of Lancaster, daughter and heiress of the Duke of Lancaster, descended legitimate male heirs, the Lancasters (King Henry IV (1399-1413), who as Henry of Bolingbroke in 1399 deposed his first cousin King Richard II (1377-1399), and was followed by his son King Henry V(1413-1422) and the latter's son King Henry VI (1422-1471). This line ended in 1471 when King Henry VI's son Edward of Westminster, Prince of Wales was killed at the Battle of Tewkesbury and when he himself was deposed
England in the Middle Ages nine months and both the English political system and the military situation in France began to unravel. A sequence of bloody civil wars, later termed the Wars of the Roses, finally broke out in 1455, spurred on by an economic crisis and a widespread perception of poor government. Edward IV, leading a faction known as the Yorkists, removed Henry from power in 1461 but by 1469 fighting recommenced as Edward, Henry, and Edward's brother George, backed by leading nobles and powerful French supporters, vied for power. By 1471 Edward was triumphant and most of his rivals were dead. On his