High Quality Content by WIKIPEDIA articles! The earliest civilizations in history were established in the region now known as the Middle East around 3500 BC, in Mesopotamia, widely regarded as the cradle of civilization. The Sumerians, Akkadians, Babylonians and Assyrians all flourished in this region. Soon after the Sumerian civilization began, the Nile River valley of ancient Egypt was unified under the Pharaohs in the 4th millennium BC, and civilization quickly spread through the Fertile Crescent to the west coast of the Mediterranean Sea and throughout the Levant. The Phoenicians, Israelites and others later built important states in this region.From the 6th century BC onwards, several empires dominated the region, beginning with the Persian Empire of the Achaemenids, followed by the Macedonian Empire founded by Alexander the Great, and successor kingdoms such as Ptolemaic Egypt and the Seleucid state in Syria. The Persian Empire was later revived by the Parthians in the 2nd century BC and continued by the Sassanids from the 2nd century AD.