The decisive showdown began when Amurru, formerly a vassal of the Hittites, allied herself with Egypt. The Hittites sought to regain control of Amurru while Egypt sought to protect her newfound territory.
The Hittite army took up position behind the tell of Qadesh. Its army included many allies from neighboring nations, which could have made maintaining control difficult. The Egyptian army consisted of Egyptian troops, with some Nubian and Sherden mercenaries as well as a contingent from Amurru.
The Hittite army hides behind the tell of Qadesh. The Egyptian army is divided into several divisions spread as far as 15 kilometers apart. Due to poor scouting and false reports Ramesses initially believed the Hittite army to be in a different location. However, he eventually learned the truth and sent riders south to quicken the advance of the Ptah division.
The Amen division begins to make camp. The Re division is attacked by 2500 Hittite chariots who crossed the river for a surprise attack. Ramesses II and his bodyguard soon find themselves fighting with their backs to the river while the Hittites pillage the Egyptian camp.
The Amurru contingent arrives and drives the Hittites from the Egyptian camp. Muwatalli II sends an additional 1000 chariots into combat, but keeps the bulk of his infantry with him on the other side of the river. However, the Hittites are obliged to retreat to Qadesh to prevent being surrounded by the approaching Ptah division. Ramesses II withdraws shortly afterwards.
The battle of Qadesh marked the end of a long rivalry between Egypt and the Hittites. Though both sides claimed victory the battle ended with no decisive victor. The Hittites retained control of Qadesh and regained control of Amurru. Additionally the Egyptian losses were substantial as about one-third of the army was lost.