a small district in the NW. corner of Mesopotamia (taken in its most extended sense), which there is some reason for supposing would be more correctly written Orrhoene.
It does not appear in any writer earlier than the times of the Antonines, and is not therefore mentioned by either Strabo or Ptolemy. Procopius states that it derived its name from a certain Osroes, who ruled there in former times (Pers.
1.17); and Dio Cassius declares that the name of the man who betrayed the Roman army under Crassus was Abgarus the Osroenian (40.19; see for the same name, 68.18, and 77.12.) Again, Herodian calls the people who dwelt in those parts Osroeni (3.9, 4.7, 7.1). Ammianus writes the name Osdroene (14.3, 8, 24.1).
The name prevailed in the country as late as the seventh century. (Hierocl. p. 713.)
In the Notitia Imperat. Osroene was placed under a “Praeses Provinciae,” and appears to have been sometimes included in Mesopotamia, sometimes kept separate from it. (See Justinian, Notit. cit. § 11; ,Joan. Malalas, xi. p. 274, ed. Bonn; Noris. de Epoch.
ii. p. 110.)
It is most likely that the correct form of the name is Orrhoene; and that this is connected with the Μαννούορρα
of Isidorus. (Stathm. Parth.
1.; and see Dion, 68.2, for the name of Mannus, a chief of the Mesopotamian Arabs, who gave himself up to Trajan.) Not impossibly the Oruros of Pliny may refer to the same district. (6.30, 119.) [EDESSA