The local deity of the city was named Ishtaran, represented on Earth by his minister, the snake god Nirah.

Ammi-Ditana of Babylon also recorded destroying the city wall of Der in his 37th year, that he said had been built earlier by Damqi-ilishu of the Sealand Dynasty.

In an inscription little known early Old Babylonian period ruler of Der, Ilum-muttabbil, claimed defeating the armies of Anshan, Elam, and Simaski, in alliance with Marhaši.

[10] Following the Persian conquest of Babylon in 539 BC, the Cyrus Cylinder mentions repatriating the people and restoring the sanctuary of the god of Der, among other cities.

[11] The site itself has been heavily damaged by water over the centuries and was considered not worth excavating.