Young King Henry enters the Parliament house, along with many lords, including Exeter, Gloucester, Winchester, Somerset, Suffolk, Warwick, and Richard Plantagenet. Gloucester tries to post a bill, but Winchester seizes it and tears it up, accusing him of coming with prewritten remarks and of being unable to speak extemporaneously. Gloucester accuses Winchester of underhanded treachery--of having plotted to kill him at London Bridge as well as at the tower. Gloucester says Winchester is greedy, but Winchester asks how he can aim so high when he is still so poor. Winchester declares that his behavior cannot be so upsetting in itself; rather, Gloucester can't stand the idea that anyone else would have influence over the king. The two men insult each other, Gloucester declaring himself as superior in his position as Protector, and Winchester declaring his own superiority as head of the Church.
The other nobles step in and stop the argument. Henry asks the two men to try to make peace, saying: "O what a scandal it is to our crown / That two such noble peers as ye should jar! / Believe me, lords, my tender years can tell / Civil dissention is a viperous worm / That gnaws at the bowels of the commonwealth"(III.i.70-73).
The mayor of London enters to tell of how Winchester and Gloucester's men, forbidden to use weapons in their conflict, now chase each other around the city, hurling rocks at each other. The battling servants enter the court, where the king orders them to cease fighting, yet they continue. Gloucester orders them to stop, and yet they still do not desist. Henry asks Winchester to order his men to yield, but Winchester says he will never yield until Gloucester submits. Gloucester offers Winchester his hand in conciliation, and after some urging by the king, Winchester agrees. They shake hands, yet mutter to themselves that the argument is not yet over.
Warwick then presents a request from Plantagenet in a scroll: Plantagenet wants to be restored to his hereditary rights. The king says that he will not only restore him to the earldom of Cambridge (inherited from his father), but he will also give him the dukedom of York (inherited from his uncle Mortimer). Plantagenet thanks the king, then kneels down to be installed as the Duke of York. Everyone cheers for him, except Somerset, who curses him under his breath.
Gloucester urges the king to cross the sea to France and be crowned as king there; he hopes this will establish English control over France once and for all. The king thanks Gloucester for his friendly counsel, and he departs with the other lords.
Exeter remains to comment on the scene. He says the nobles will march to France blindly: they do not see that these disagreements between the lords, now reduced to a slow burn, will someday break into open flame (This could likely happen in France, where the English will need all the strength of unity). And just as parts of a dead body rot little by little, so this discord will slowly destroy the kingdom. He refers to a prophecy once widely circulated in the time of Henry V, that Henry V should win everything, while Henry VI would lose it all. Exeter wishes he might die before he sees such unhappy conclusions.