Henry VII (of England), often called Henry Tudor (1457­1509), king of England (1485­1509) and first ruler of the house of Tudor, whose reign initiated a period of national unity following the strife of the 15th century. Henry, the son of Edmund Tudor, earl of Richmond (1430?­56), and Margaret Beaufort, countess of Richmond and Derby (a direct descendant of John of Gaunt, duke of Lancaster), was born on January 28, 1457, in Pembroke Castle, Pembrokeshire. After the Yorkist king Edward IV seized the throne from the Lancastrian Henry VI in 1471, Henry Tudor, a Lancastrian, took refuge in Brittany. He became head of the house of Lancaster on the death of Henry VI in the same year. In 1483, taking advantage of the indignation aroused against Edward's successor, Richard III, whose nephews, Edward V and Richard, duke of York (1472­83), were murdered in the Tower of London, presumably on Richard's order, Henry crossed over to Wales, where he gathered an army of supporters. In 1485, at Bosworth Field in England, he met and defeated Richard, who was killed during the battle. Henry Tudor was subsequently crowned Henry VII in London. In the following year he married the Yorkist heiress, Elizabeth (1465­1503), eldest daughter of Edward IV, uniting the houses of York and Lancaster and ending the Wars of the Roses. After his accession Henry had to contend with several Yorkist uprisings, notably one led by the English impostor Lambert Simnel (circa 1471­1534), who claimed to be Edward, earl of Warwick (1475­99), the last Yorkist claimant to the throne. The real earl of Warwick was actually imprisoned by Henry in the Tower of London at the time. Another revolt was led by the Walloon impostor Perkin Warbeck, who claimed to be Richard, duke of York, the younger of the murdered sons of Edward IV. Although both impostors had strong backing in England and abroad, their forces were defeated by Henry. In 1494 Henry sent the English statesman Sir Edward Poynings (1459­1521) to Ireland to reestablish English control in that country. Henry managed to maintain peaceful relations with Austria, Spain, and France throughout most of his years as king. The reorganization in 1487 of the Star Chamber was one of several means by which Henry strengthened the royal power over the nobles. He died in Richmond, Surrey, on April 21, 1509, and was succeeded by his second son, Henry VIII.