Starting as a small settlement in the seventh millennium BC, Tell Brak evolved during the fourth millennium BC into one of the biggest cities in Upper Mesopotamia, and interacted with the cultures of southern Mesopotamia. The city shrank in size at the beginning of the third millennium BC with the end of Uruk period, before expanding again around c. 2600 BC, when it became known as Nagar, and was the capital of a regional kingdom that controlled the Khabur river valley. Nagar was destroyed around c. 2300 BC, and came under the rule of the Akkadian Empire, followed by a period of independence as a Hurrian city-state, before contracting at the beginning of the second millennium BC. Nagar prospered again by the 19th century BC, and came under the rule of different regional powers. In c. 1500 BC, Tell Brak was a center of Mitanni before being destroyed by Assyria c. 1300 BC. The city never regained its former importance, remaining as a small settlement, and abandoned at some points of its history, until disappearing from records during the early Abbasid era.