We present the results of accelerator mass spectrometry (AMS) radiocarbon dating of 11 samples collected from 4 locations in southern Iraq. As a result of the hiatus in fieldwork in that region since 1990, and the antiquity of the majority of archaeological excavations conducted there, the record of 14C dates for southern Mesopotamia is patchy for all periods. This is especially true for the mid-Holocene, when the world's oldest and longest-sustained urban system first emerged there. The dates here reported not only make a significant contribution to available dates for this important region and period; they fill specific gaps in crucial geographic coverage, and shed light on the extent of marshland boundaries and the antiquity of settlement at key urban centers.