This article presents some reflections on slavery in the Ancient Near East during the Old Babylonian period. Particular attention is paid to an analysis of the sources for prisoners of war originating from Uruk in which the bīt asīrī, “the house of prisoners of war” is mentioned. These texts from the bīt asīrī date to the short reign of Rīm-Anum, who held power in Uruk for about eighteen months, between 1742 and 1740 BC. The use of war prisoners as labor force and slaves is examined in detail. It is suggested that the bīt asīrī was an institutional entity, managed by the state, and moreover that it was connected with the production of flour. This investigation also makes comparisons with other references to prisons in the Ancient Near East and especially in the Bible. Lastly, the ways in which war captives could be freed are discussed.