The original homeland of the Kassites is not well established, but appears to have been located in the Zagros Mountains, in what is now the Lorestan Province of Iran. However, the Kassites were—like the Elamites, Gutians and Manneans who preceded them—linguistically unrelated to the Iranian-speaking peoples who came to dominate the region a millennium later. They first appeared in the annals of history in the 18th century BC when they attacked Babylonia in the 9th year of the reign of Samsu-iluna (reigned 1749-1712 BC), the son of Hammurabi. Samsu-iluna repelled them, as did Abi-Eshuh, but they subsequently gained control of Babylonia in 1570 BC, some 25 years after the fall of Babylon to the Hittites in 1595 BC, and went on to conquer the southern part of Mesopotamia, roughly corresponding to ancient Sumer and known as the Dynasty of the Sealand by 1520 BC. The Hittites had carried off the idol of the god Marduk, but the Kassite rulers regained possession, returned Marduk to Babylon, and made him the equal of the Kassite Shuqamuna. The circumstances of their rise to power are unknown, due to a lack of documentation from this so-called Dark Age period of widespread dislocation. No inscription or document in the Kassite language has been preserved, an absence that cannot be purely accidental, suggesting a severe regression of literacy in official circles. Babylon under Kassite rulers, who renamed the city Karanduniash, re-emerged as a political and military power in Mesopotamia. A newly built capital city Dur-Kurigalzu was named in honour of Kurigalzu I (early 14th century BC).