The Akkadian Empire (2350-2150 BCE), the first empire in history.

In 2340 BC Sargon of Akkad conquered most of the Sumerian city-states, thus ending Sumer with the rise of the Akkadian Empire, sometimes regarded as the first empire in history. The Akkadians were a Semitic-speaking group who united the Semites and Sumerian speakers under one rule. Akkadian gradually replaced Sumerian as a spoken language somewhere around the turn of the 3rd and the 2nd millennia BC. The Akkadian empire was short-lived and in 2125 BC the empire fell. Mesopotamia eventually coalesced into two distinct empires: Assyria in the north and Babylonia in the south.
After the fall of the Akkadian Empire, the Akkadian people of Mesopotamia eventually coalesced into two major Akkadian speaking nations: Assyria in the north, and, a few centuries later, Babylonia in the south.