Charles IV the Fair died without an heir in 1328. Under the rules of the Salic law the crown of France could not pass to a woman nor could the line of kingship pass through the female line. Accordingly, the crown passed to Philip of Valois, rather than through the female line to Edward of Plantagenet, who would soon become Edward III of England. During the reign of Philip of Valois, the French monarchy reached the height of its medieval power. However Philip's seat on the throne was contested by Edward III of England in 1337, and England and France entered the off-and-on Hundred Years' War.  The exact boundaries changed greatly with time, but landholdings inside France by the English Kings remained extensive for decades. With charismatic leaders, such as Joan of Arc and La Hire, strong French counterattacks won back most English continental territories. Like the rest of Europe, France was struck by the Black Death; half of the 17 million population of France died.