Final answer:
The ruler of Akkad before Sargon was Lugal-Zage-Si. Sargon of Akkad established the Akkadian Empire, the world's first-known empire, and was succeeded by the Third Dynasty of Ur under Ur-Nammu.
Step-by-step explanation:
The ruler of Akkad before Sargon was Lugal-Zage-Si. Sargon is credited with establishing the first-known empire in world history, the Akkadian Empire, around 2340 BCE and creating the world's first standing army. He conquered and united the city-states of Sumer, and later his empire expanded to include regions such as northern Iraq, Syria, and southwestern Iran. His empire lasted for about a century and a half and officially came to an end in 2193 BCE. Notably, Sargon's administrative techniques became a model for subsequent rulers, and the Third Dynasty of Ur later united Sumer using similar methods under the rule of Ur-Nammu.