Marduk-apla-uṣur, inscribed dAMAR.UTU-A-ŠE[Š],[i 1] or mdŠID-A-[x],[i 2] meaning 'O Marduk, protect the heir' was an 8th century BC Chaldean tribal leader who ruled as King of Babylon after the reign of Marduk-bēl-zēri.
[1]: 215 He should not be confused with the Marduk-apla-uṣur who ruled Suḫi on the middle Euphrates and paid tribute to Salmānu-ašarēdu III a generation or so earlier.
Into the vacuum created by the devastation, the southern Chaldeans were able to rise to power and he seems to have been the first member of the tribal group to have made pretensions to the Babylonian throne.
Its kingship was transferred to the Sealand,"[i 1] and, as his successor was Erība-Marduk, the archetypal ancestor figure of the later Chaldean monarchs, it is surmised his origins were with a different Chaldean group than that of Erība-Marduk's Bīt-Yakin tribe.
He is mentioned in a fragmentary Neo-Babylonian narrative text from Uruk[i 3] ("The Crimes and Sacrileges of Nabu-šuma-iškun") which provides no further enlightenment about his time apart from a passing observation that "forced labor and corvée were imposed.