Osroene (also spelled Osrohene, Osrhoene, from the Greek Όσροηνῆ; Syriac: ܡܠܟܘܬܐ ܕܒܝܬ ܥܣܪܐ ܥܝܢܐ Malkuṯā d-Bēt ʿŌsrā ʿĪnē), also known by the name of its capital city, Edessa (modern Şanlıurfa, Turkey), was a historic kingdom located on the present-day border of Syria and Turkey. The kingdom was Assyrian and enjoyed semi-autonomy to complete independence from the years of 132 BCE to 244 AD. It was a Syriac speaking kingdom, and according to an ancient legend King Abgar V of Edessa was converted to Christianity by Thaddeus of Edessa, or Saint Addai, one of the Seventy-two Disciples. By 201 AD or earlier, under King Abgar the Great, Osroene became the first Christian state.
- Parpola, Simo. "Assyrian Identity in Ancient Times and Today" (PDF). Assyriologist. Journal of Assyrian Academic Studies. p. 15.
When the Seleucid Empire disintegrated at the end of the second century BC, its western remnants were annexed to Rome, while several semi-independent kingdoms of decidedly Assyrian identity (Osroene, Adiabene, Hatra, Assur) popped up in the east under Parthian overlordship.
- The Revival of Spiritual Healing, by Barsom J. Kashish, 2002, p. 217
- Alexander Roberts & James Donaldson Eds. The Writings of the Fathers Down to AD 325: Ante-Nicene Fathers vol. 8 (Peabody, Massachusetts: Hendrickson Publishers, 1994), 657-672. 
- The Ancient Name of Edessa, Amir Harrak, Journal of Near Eastern Studies, Vol. 51, No. 3 (Jul., 1992), pp. 209-214 
- Herbermann, Charles George (1913). The Catholic Encyclopedia. Encyclopedia Press. p. 282.
- von Harnack, Adolph (1905). The Expansion of Christianity in the First Three Centuries. Williams & Norgate. p. 293.
there is no doubt that even before 190 A.D. Christianity had spread vigorously within Edessa and its surroundings and that (shortly after 201 or even earlier?) the royal house joined the church
- Adshead, Samuel Adrian Miles (2000). China in World History. Macmillan. p. 27. ISBN 978-0-312-22565-0.
- Cheetham, Samuel (1905). A History of the Christian Church During the First Six Centuries. Macmillan and Co. p. 58.
- Lockyer, Herbert (1988). All the Apostles of the Bible. Zondervan. p. 260. ISBN 978-0-310-28011-8.