 The northern border is somewhat uncertain but probably went along a line from Anta to Takrīt.Ḥīra was probably the southernmost point, the border then following the northern part of the swamps of Wasit.The Parthians had exercised only loose control at times, allowing for a number of Syriac-speaking Assyrian kingdoms to flourish in Upper Mesopotamia, the independent Osroene, as well as the districts of Adiabene and the partly Assyrian state of Hatra.