Hammurabi did not fight any important wars in the early part of his reign. He instead improved the buildings of Babylon. He built taller city walls to make the city more difficult to attack, and expanded the temples. In around 1771 BC, the kingdom of Elam attacked Mesopotamia from the east. Elam invaded Eshnunna, a city-state to the north-east of Babylon, and destroyed its cities. It also tried to start a war between Babylon and Larsa, a city in southern Mesopotamia. However, Hammurabi instead made an alliance with Larsa against Elam. Hammurabi defeated Elam, but felt that Larsa had not given him enough help. He therefore attacked Larsa. Babylon had entirely conquered southern Mesopotamia by c. 1763 BC.