The duration of Nebuchadnezzar's war with Elam and the number of campaigns he conducted are not known, though it is reasonable to believe that this was a protracted effort with diverse strategic considerations. According to a later literary tradition, an invasion of Elam was thwarted when his army was struck by plague and he narrowly escaped death in the stampede to return home. A raid, or "šiḫṭu", commemorated in a "kudurru" created during his reign describes a successful campaign. In this raid he was accompanied by the Kassite chieftain Šitti-Marduk who struck the decisive blow, he was able to overrun Elam in a surprise attack conducted from Dēr during the hottest of the summer months, Dumuzi, when