Warwick receives news from messengers about the arrival of Montague and George's troops. Then, Edward and Richard arrive with their troops. Edward asks Warwick if he will support Edward as king, but Warwick says he should remain Duke of York. Warwick says his efforts got Edward the kingdom in the first place, but Warwick's preferred king is now Henry. Edward reveals that Henry has been imprisoned.
Oxford arrives with troops to aid Warwick, followed by Montague, Somerset, and even George. Edward asks George if even he will fight against his brother. Richard and George confer, and George announces he will break with Warwick. He asks his brothers to forgive him, and they do. Edward asks Warwick if his troops will come out and fight, and Warwick agrees to battle.
During battle, Edward drags in a wounded Warwick and leaves him. Warwick knows he has been felled, like a giant tree that has shaded the monarchy under his protection all the while. Of all his lands, he thinks, nothing remains but that bit of earth on which he lies. Somerset and Oxford enter to tell Warwick that Margaret has arrived from France with a powerful army. Somerset reports the death of Montague, and Warwick dies.
Edward enters to triumph with his brothers Richard and George. They have beaten Warwick's forces, but Margaret's troops approach. They discuss their numbers of soldiers and her forces and set off for the battlefield.
Margaret enters with Prince Edward, Somerset, and Oxford. She urges her troops on, speaking of their efforts as those of a crew on a ship, whose captain is gone, many sailors lost, and masts damaged--yet they bravely continue. Even if Warwick and Montague, important parts of their force, are gone, Oxford and Somerset can be another anchor or another mast. We should forge ahead, she says, for Edward, George, and Richard are but rough seas and sharp rocks, who will have no mercy for any who might think to flee.
Prince Edward thinks even a coward hearing these words would become brave. He urges any who are frightened to leave. Oxford marvels that a woman and a young man can be so much more courageous than soldiers. A messenger enters to announce the approach of Edward.