In 1485 Henry Tudor, Duke of Richmond (Henry VII to be), defeated Richard III at the Battle of Bosworth Field to seize the crown. He pardoned all those who have fought for Richard III who were willing to recognise his claim to the throne. Then he acted quickly against his remaining opponents by taking an army to the North.  He finished the War of the Roses for ever by getting married to Elizabeth of York (the niece of Richard III and daughter of Edward IV), thus uniting the houses of Lancaster and York to form the Tudor dynasty. The Yeomen of the Guard ("a group of hardy, strong and agile archers"), were formed at this time as a personal bodyguard for the king. He is known for improving the administration of the country. After making peace with France, the economy improved by the opening of French markets. He also forbade the nobility from having any retainers other than household servants. This weakened these regional magnates, who had been virtual kings in their own lands, by reducing the number of men they could call on to revolt against the King. There were, however, a number of rebellions during this reign, one led by Lambert Simnel (claiming to be Edward V the eldest son of Edward IV ) and another by Perkin Warbeck (claiming to be the surviving Richard Duke of York, the younger son). These two boys (the Princes in the tower) were reported murdered by Richard III, their uncle, years before. Henry VII's daughter Margaret Tudor was married (1503) to the King James V of Scotland as part of a plan to remove the Scottish support for Perkin Warbeck. Henry VII encouraged exploration and sponsored the voyages of the John & Sebastion Cabot in the search for a north-west passage to the Indies. He secured a successful marriage for his eldest son, Arthur Prince of Wales, to Catherine of Aragon, the Infanta of .Aragon, daughter of the the King Ferdinand V and Queen Isabella of Spain (Aragon and Castile). One recurring theme in early Tudor policy was a need to produce a male heir which would allow continuing peace rather than a return to civil war. On the death of Elizabeth, his queen, he unsuccessfully searched for a new wife, looking for alliances on the continent of Europe. Prince Arthur died before his father. On the death of their father, Henry VII, his younger brother Henry became King Henry VIII. Famous English people during this reign include: John Morton (1420-1500) who became Lord Chancellor and Archbishop of Canterbury in 1486; Polidore Vergil (1470-1555) (an Italian by birth) came to England in 1502, wrote Anglica Historia - a history of England, William Caxton (1422?-1491) , who printed the first book in English in 1474.