This illustration is a great one. It reminds me of Elizabeth I in the film, when she gave her speech to the army: I may have the body of a woman but I have the heart and stomach of a man.
The two Despensers' hold over King Edward II not only caused resentment among the barons and the court, but, understandably, with the queen. Isabella was the sister of the king of France, Charles IV. When a dispute arose between England and France over Gascony, Isabella managed to persuade the king to send her to her brother to make peace, and so escaped from court and from England.