Claudioupolis of Honorias (Byzantium)

1. Geographical position

Claudioupolis was a city in the province of Honorias between Nicomedia and Krateia. In the Roman and the Early Byzantine period the city was a mansio, meaning a mail station, along the road leading from Nicomedia to Krateia and Gangra before reaching Neocaesarea. This road served both the mail and the traders, but was mainly a military road. To the south Claudioupolis was directly connected with Modrine and, via Krateia, with Ankyra, while to the north there was its harbour. Ruins of the wall and the settlement of Byzantine Claudioupolis have survived in modern Hali Hisar, a position where the settlement was transferred in the 12th century, 6 km NW of the former position, where the modern Turkish city of Bolu stands.

2. History

The city first appears in the Byzantine sources in 388, when Emperor Theodosius I (379-395) demanded that the curiales of Claudioupolis, Prusias, Tottaion and Doris should pay an additional tax in order to cover the expenses of corn supplies transported by sea to the military camps of the empire. Claudioupolis, ancient Bithynion, belonged to the province of Bithynia-Pontus. In the early 5th century it came under the new province of Honorias, which was established in the lands of Bithynia and Paphlagonia, and served as the seat of the praeses of the province and the metropolitan of Claudioupolis. In the Synekdemos of Hierokles (6th c.), it is reported as one of the six cities of Honorias. In 535 the city was incorporated into the wider province of Paphlagonia and later again into the province of Honorias. In the Middle Byzantine period, Claudioupolis initially belonged to the theme of Opsikion. In the second half of the 9th century it was the seat of one of the two tourmai of the theme of Boukellarion, as evidenced by the seal of Eustathios, imperial strator and tourmarch of Claudioupolis.

In 967 Claudioupolis, described by the Byzantine historian Leo the Deacon as “the most blissful region of Galatia”,1 was struck by a huge earthquake. In the first half of the 11th century it was, along with Krateia, the area of jurisdiction of an imperial official,2 probably a dioiketes. Then, in the second half of the 11th century, the Türkmen and the Seljuk Turks invaded the hinterland of Asia Minor. In the 12th century the inhabitants of Claudioupolis transferred the settlement 6 km NW of its former position, in a nearby forest, where they built a castle. Claudioupolis at the time was in the line of conflict between the Danismendids and the Seljuks. In the winter of 1179-80, while Claudioupolis was blockaded by the Türkmen, Emperor Manuel I Komnenos ran to help the besieged castle, relieved it from the siege and destroyed the enemy’s camp. However, Claudioupolis later fell in the hands of the Seljuks, certainly before 1214.3 It is very likely that in the 14th century Claudioupolis was occupied by the Ottomans.




1. Λέων Διάκονος, Ιστορία, Hase, C.B. (ed.), Leonis Diaconi Caloensis Historie libri decem et liber de velitatione bellica Nicephori Augusti (Corpus Scriptorum Historiae Byzantinae, Bonn 1828), p. 68, 5-6: Κλαυδιούπολίν τε, τ ε δαιμονέστατον χωρίον τν Γαλατν...” (Claudioupolis, the most blissful region of Galatia).

2. Zacos, G. - Veglery, A., Byzantine Lead Seals 1 (Basel 1972), no. 970.

3. In 1214, Theodore I Laskaris (1204-1222) consolidated his power in the region of Honorias. The fact that Claudioupolis is nowhere reported in the sources after that year indicates that the city had previously been in the hands of Muslims.