The Egypto-Hittite Empire

In the 1320s BC, Tutankhamun, Pharaoh of Egypt, died. His widow, Ankhesenamun, sent a letter to the Hittite king, asking to marry one of his sons. He sent over his son, Zannanza, to marry her, but he died on the way. He accused the new Egyptian Pharaoh Ay of killing him. This led to a war between the two nations. But what if that hadn't happened? What if Zannanza became Pharaoh and later King of the Hittites uniting the two nations into a formidable empire?
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