With Jon Connington disgraced and exiled and Ser Barristan Selmy urging that the crown gather its full strength, King Aerys at last summoned his son and heir home from wherever he had hidden the Lady Lyanna Stark and gave Prince Rhaegar Targaryen command of the royal host. Rhaegar mustered a great army of loyalists, the marcher lords, the men of the crownlands, and the Dornish spears of Prince Lewyn Martell of the Kingsguard among them, and marched north to meet the joined rebel host before it could cross the Trident and threaten King's Landing. The two armies came together at the ford of the Green Fork that men would ever after call the ruby ford, and there the war was decided.
The fighting was long and bloody, and the rebels held the field only because their leaders bore the weight of it themselves. Lord Eddard Stark commanded the northern host, Lord Jon Arryn and Lord Hoster Tully their own, and Ser Barristan Selmy carved a red path through the rebel ranks before he was struck down and, later, spared for his valor. In the end it came to Robert Baratheon and Rhaegar Targaryen, prince and lord, who met at last amid the running water. With his great warhammer Robert dealt Rhaegar a mortal blow that shattered the rubies from the prince's black armor and scattered them glittering across the ford, whence its name. When Rhaegar fell the loyalist heart failed with him, and the host broke and fled. Robert himself was gravely wounded and left the pursuit to others, but the crown's cause never recovered from the death of its finest prince, and the road to King's Landing lay open.