On January 18, 1486 the Royal Houses of Lancaster and York were united by the marriage of Henry VII to Elizabeth of York, the eldest daughter of Edward IV. Henry seized the crown on August 22, 1485 and reigned until his death on April 21, 1509, as he was the first monarch of the House of Tudor. Henry won the throne when he defeated Richard III at the Battle of Bosworth Field. He was the last king of England to win his throne on the field of battle. He was successful in restoring the power and stability of the English monarchy after the political upheavals of the Wars of the Roses. He founded a long-lasting dynasty and, after a reign of nearly 24 years, was peacefully succeeded by his son, Henry VIII.