The ancient Sumerian king who issued the law favoring the imposition of justice instead of naked vengeance was King Ur-Nammu of Ur, who reigned circa 2112–2095 BCE. He is credited with creating the Code of Ur-Nammu , the oldest known surviving law code, which established legal principles emphasizing equity, restitution, and justice rather than mere retaliation or blood vengeance

. The prologue of the Code of Ur-Nammu explicitly states that the king "established equity in the land," banishing violence and strife, and protecting the weak such as orphans and widows from exploitation by the powerful. Unlike later codes such as the Babylonian Code of Hammurabi, which is famous for the lex talionis ("eye for an eye") principle, Ur-Nammu's code often prescribed monetary fines and compensation for bodily harm rather than physical punishment or revenge. This reflects a legal philosophy that favored restoring social order and justice over exacting personal vengeance

. Thus, King Ur-Nammu stands as the pioneering ruler who codified laws to impose justice in a structured, equitable manner in ancient Sumer.