the home of William Herbert, Earl of Pembroke, a leading Yorkist. Following the murder of Henry VI and death of his son, Edward, in 1471, Henry became the person upon whom the Lancastrian cause rested. Concerned for his young nephew's life, Jasper Tudor took Henry to Brittany for safety. Lady Margaret remained in England and remarried, living quietly while advancing the Lancastrian (and her son's) cause. Capitalizing on the growing unpopularity of Richard III (King of England from 1483), she was able to forge an alliance with discontented Yorkists in support of her son. Two years after Richard III was crowned, Henry and Jasper sailed from the mouth of the Seine to the Milford Haven Waterway and defeated Richard III at the Battle of Bosworth Field (22 August 1485). Upon this victory, Henry Tudor proclaimed himself King Henry VII. Henry VII Upon becoming king in 1485, Henry VII moved rapidly to secure his hold on the throne. On 18 January 1486 at Westminster, he honoured a pledge made three years earlier and married Elizabeth of York (daughter of King Edward IV). They were third cousins, as both were great-great-grandchildren of John of Gaunt. The marriage unified the warring houses of Lancaster and York and gave the couple's children a strong claim to the throne. The unification of the two houses through this marriage is symbolized by the heraldic emblem of the Tudor rose, a combination of the white rose of York and the red rose of Lancaster. Henry VII and Elizabeth of York had several children, four of whom survived infancy: Arthur, Prince of Wales (born 1486, died 1502) Henry, Duke of York (born 1491, died 1547) Margaret (born 1489, died 1541), who married James IV of Scotland Mary (born 1496, died 1533), who married Louis XII of France Henry VII's foreign policy had an objective of dynastic security: witness the alliance forged with the marriage in 1503 of his daughter Margaret to James IV of Scotland and through the marriage of his eldest son. In 1501 Henry VII married his son Arthur to Catherine of Aragon, cementing an alliance with the Spanish monarchs, Ferdinand II of Aragon and Isabella I of Castile. The newlyweds spent their honeymoon at Ludlow Castle, the traditional seat of the Prince of Wales. However, four months after the marriage, Arthur died, leaving his younger brother Henry as heir apparent. Henry VII acquired a papal