A History of the British Monarchy/Lancastrian Rulers

The House of Lancaster was descended from John of Gaunt, third son of Edward III. Henry IV ousted his cousin Richard II (descended from Edward III's second son) and Richard's son Edmund Mortimer to seize the throne. The reign of Henry VI was interrupted during the Wars of the Roses. Lancastrian Rulers of England /Henry IV/ (r. 1399 - 1413) /Henry V/ (r. 1413 - 1422) /Henry VI/ (r. 1422 - 1461, and 1470 - 1471)