Abonoteichos (Greek: Ἀβώνου τεῖχος Avónou tíchos, demonym: Ἀβωνοτειχίτης Avonotichítis), later Ionopolis (Ἰωνόπολις Ionópolis; Turkish: İnebolu), was an ancient city in Asia Minor, on the site of modern İnebolu (in Asian Turkey) and remains a Latin Catholic titular see.
Abonoteichos was a town on the coast of Paphlagonia, memorable as the birthplace of the impostor Alexander, founder of the cult of Glycon, of whom Lucian has left us an amusing account in the treatise bearing his name. According to Lucian, Alexander petitioned the Roman emperor (probably Antoninus Pius) that the name of his native place should be changed from Abonoteichos to Ionopolis; and whether the emperor granted the request or not, we know that the town was called Ionopolis in later times.
Not only does this name occur in Marcian of Heraclea and Hierocles, but on coins of the time of Antoninus and Lucius Verus we find the legend Ionopoliton (Ἰωνοπολιτῶν, Ionopoliton), as well as Abonoteichiton (Ἀβωνοτειχιτῶν, Avonotichiton). The modern Turkish name İnebolu is evidently only a corruption of Ionopolis.
Ecclesiastical history of Ionopolis
It was important enough in the Roman province of Paphlagonia to become a suffragan bishopric of the Metropolitan of its capital Gangra, but faded later. Michael LeQuien mentions eight bishops between 325 and 878 and Ionopolis is mentioned in the later “Notitiae episcopatuum.” 
- Petronius of Ionopolis was at the Council of Nicaea 
- Rhenus, at the Council of Chalcedon
- Diogenes of Ionopolis, at Council of Ephesus 
- .....ios, bishop of Ionopolis. (known only from a 10th century coin)
- Niketas, bishop of Ionopolis and chartoularios of the Great Orphanotropheion. 11th century 
- John, bishop of Ionopolis 11th century
Catholic titular see
It has been vacant for decades, having had the following incumbents, both of the lowest (episcopal) and intermediary (archiepiscopal) ranks :
- Titular Bishop Wilhelm Hermann Ignaz Ferdinand von Wolf-Metternich zu Gracht (1720.09.16 – 1722.10.28)
- Titular Bishop Joannes Karski (1771.07.29 – 1785)
- Titular Bishop Bishop-elect John Murphy (1815.02.21 – 1815.02.21)
- Titular Bishop Bishop-elect Ferdinand Corbi (1833.09.30 – ?)
- Titular Bishop Wincenty Lipski (1856.09.18 – 1875.12.13)
- Titular Archbishop James Gibbons (1877.05.29 – 1877.10.03), previously Titular Bishop of Adramyttium (1868.03.03 – 1872.07.30) & Apostolic Vicar of North Carolina (USA) (1868.03.03 – 1877.05.20), also Bishop of Richmond (USA) (1872.07.30 – 1877.05.29); later Coadjutor Archbishop of Baltimore (USA) (1877.05.29 – 1877.10.03), succeeding as Metropolitan Archbishop of Baltimore (1877.10.03 – 1921.03.24), Cardinal-Priest of S. Maria in Trastevere (1887.03.17 – 1921.03.24), becoming Protopriest of the Sacred College of Cardinals (1920.12.07 – 1921.03.24)
- Titular Archbishop Francis Xavier Leray (1879.09.30 – 1883.12.28)
- Titular Bishop Giacomo Daddi (1884.03.24 – 1897?)
- Titular Bishop Andrea Cassato (1898.03.24 – 1913.05.01)
- Titular Bishop Henri Doulcet, Passionists (C.P.) (1913.06.03 – 1914.03.17); previously Bishop of Nikopol (Bulgaria) (1895.01.07 – 1913.03.31); later Titular Archbishop of Dioclea (1914.03.17 – 1916.07.27)
- Titular Bishop Joseph John Fox (1914.11.07 – 1915.03.14)
- Titular Bishop Nicolás Gonzalez Pérez, Claretians (C.M.F.) (1918.08.24 – 1935.03.23)
- Titular Bishop Eugène-Louis-Marie Le Fer de la Motte (1935.07.08 – 1936.07.20)
- Titular Bishop Johann Baptist Dietz (1936.07.25 – 1939.04.10), Coadjutor Bishop of Fulda (Germany) (1936.07.25 – 1939.04.10), succeeding as Bishop of Fulda (1939.04.10 – 1958.10.24), later Titular Archbishop of Cotrada (1958.10.24 – 1959.12.10)
- Titular Bishop Maurice-Auguste-Eugène Foin (1939.06.10 – 1948.07.10)
- Titular Bishop Hubert Joseph Paulissen, Society of African Missions (S.M.A.) (1951.11.15 – 1966.08.12)
- Smith, William (1857), "Abonoteichos", in Smith, William, Dictionary of Greek and Roman Geography, 1, London: Walton & Maberly, p. 5
- Lucian, Alex § 58
- Marcian of Heraclea, Peripl. p. 72
- Synecdemus, p. 696
- Strabo, p. 545
- Arrian, Periplus Ponti Euxini p. 15
- Ptol. v. 4 § 2
- Stephanus of Byzantium, s. v. Ἀβώνου τείχος
- Herbermann, Charles, ed. (1913). "Ionopolis". Catholic Encyclopedia. New York: Robert Appleton Company.
- Louis Vivien de Saint-Martin , Historical and geographical description of Asia Minor, including ancient times, the Middle Ages and modern times (A. Bertrand, 1845) p436
- Le Quien, Oriens Christ., I, 555
- CUINET, La Turquie d'Asie, IV (Paris, 1894), p466-69.
- The Catholic Encyclopedia (1908.
- Roderic Mullen, The expansion of Christianity (Brill, 2004) p. 123.
- Richard Price, Michael Gaddis, The Acts of the Council of Chalcedon, Volume 1 (Liverpool University press, 2005) p88.
- Eduard Schwartz, Collectio Novariensis de re Eutychis (Walter de Gruyter, 1 July 1962) p207.
- N. bishop of Ionopolis (tenth century) .
- Jean-Claude Cheynet, Studies in Byzantine Sigillography, Volume 8 (Walter de Gruyter, 2003)p58.
- [http://www.doaks.org/resources/seals/byzantine-seals/BZS.1922.214.171.1242 Niketas bishop of Ionopolis (and chartoularios) of the Great Orphanotropheion (eleventh century).
- Elizabeth Jeffreys, John F. Haldon, Robin Cormack, The Oxford Handbook of Byzantine Studies (Oxford University Press, 2008) p154.
- John bishop of Ionopolis (eleventh century) .
- Dumbarton Oaks, John W. Nesbitt, Eric McGeer, Nicolas Oikonomidès, Catalogue of Byzantine Seals at Dumbarton Oaks and in the Fogg Museum of Art: The East (Dumbarton Oaks, 2001) p49-50.
- Hierarchia Catholica, Volume 5, Page 229
- Les Ordinations Épiscopales, Year 1721, Number 6.
- Hierarchia Catholica, Volume 6, Page 244, and Page 454.
- Les Ordinations Épiscopales, Year 1772, Number 34.
- Le Petit Episcopologe, Issue 178, Number 14.787
- Hierarchia Catholica, Volume 8, Page 323.
- This article incorporates text from a publication now in the public domain: Smith, William, ed. (1854). "Aboni-Teichos". Dictionary of Greek and Roman Geography. 1. London: John Murray. p. 5.