King Louis of France enters his throne room with Lady Bona, Prince Edward, Margaret, and Oxford. Louis bids Margaret to sit by him and tell him of her troubles. She relates Henrys misfortune, that he has fled to Scotland while Edward has taken the throne. With her son, she begs Louis aid.
Then, Warwick enters. He announces his greetings from Edward and asks Louis to grant the hand of Lady Bona to Edward. Margaret interrupts to declare that Edward is a tyrant, for tyrants always want to make allies abroad so they may safely rule at home. Henry still lives, she reminds Louis, as does his son. So, Edward is only a usurper. Warwick brings up the past, repeating the claim that Henry is a usurper, since his grandfather took the throne illegally from Richard II. Warwick and Oxford argue. Louis asks to speak to Warwick alone.
Louis asks Warwick if Edward is legally installed as king and if he genuinely loves Lady Bona. Warwick assures him of Edward's solidity and his love for Lady Bona. Louis decides to give her to Edward, and he tells Margaret and her followers. Louis explains that Henrys claim to the throne seems weak, since he was ousted; thus, he supports Edward.
A messenger enters with letters. Louis reads that Edward has married Lady Gray and has scorned a marriage with Lady Bona and an alliance with France. Warwick tells Louis that Edward has dishonored him by having sent him to France to negotiate for a wife, then marrying someone else. He renounces Edward and declares that he will return to Henrys allegiance. He asks Margaret to forgive him, and she does.
Warwick asks Louis to lend some soldiers to force Edward from the throne. He has heard that George is also likely to break with his brother, strengthening their cause. Louis agrees. They send messages to Edward; Margaret announces that she puts on armor again, and Warwick declares he has been wronged and will see Edward uncrowned soon. Warwick offers Margaret assurance that he supports her by offering his daughter in marriage to Prince Edward.
Warwick, alone, considers his journey; he came as an ambassador for Edward but returns an enemy. He was the chief supporter of Edward in his rise to the throne, and now he will be the main impetus in his fall, declares Warwick.