In the medieval and Tudor world there was no question in people's minds about the order of God's creation — men ruled and women didn't. A king was a warrior who literally fought to win power then battled to keep it. Yet despite everything that stood in their way, a handful of extraordinary women did attempt to rule medieval and Tudor England. In this series, historian Dr Helen Castor explores seven queens who challenged male power, the fierce reactions they provoked and whether the term "she wolves" was deserved. In 1308 a 12-year-old girl, Isabella of France, became queen of England when she married the English king. A century later another young French girl, Margaret of Anjou, followed in her footsteps. Both these women were thrust into a violent and dysfunctional England and both felt driven to take control of the kingdom themselves. Isabella would be accused of murder and Margaret of destructive ambition — it was Margaret who Shakespeare named the She Wolf. But as Helen reveals, their self-assertion that would have seemed natural in a man was deemed unnatural, even monstrous in a woman.