 Edward strengthened his claim with a decisive victory at the Battle of Towton in the same year, in the course of which the Lancastrian army was virtually wiped out.The early reign of Edward IV was marred by Lancastrian plotting and uprisings in favour of Henry VI.Warwick himself changed sides, and supported Margaret of Anjou and the king's jealous brother George, Duke of Clarence, in briefly restoring Henry in 1470–71.