Pek çok kez değişikliğe uğramış olmakla birlikte ; doğuda Vezirköprü çevresi, güneyde Çankırı il merkezindeki antik Gangra kenti dolayları ve batıda da Gerede civarına değin uzanan antik Paphlagonia bölgesi kuzeyde ise Karadeniz tarafından sınırlandırılmaktadır. Paleolitik dönemden itibaren yerleşime sahne olduğu bilinen bölge, özellikle Hititler döneminde Gasga ve Pala kavimleri dolayısıyla kaynaklarda da tanınmaya başlamıştır. Öncüllerinin kimler olduğu net olarak bilinemeyen Paphlagonların, M.Ö.1200 dolaylarındaki kavimler göçü esnasında Anadolu'ya gelmiş Trakya kökenli halklardan oldukları görüşü genelde kabul edilmekle birlikte Anadolu'nun yerel toplumlarıyla bağlantılarının olduğu muhtemeldir.

The ancient city of Pompeiopolis takes place on the north side of Taşköprü that is 45 km. northeast of Kastamonu. Two hills which the higher of them called as Zımbıllı Tepesi and had been served as an acropolis. The Amnias (Gökırmak) valley which Pompeiopolis took place in, has a very long and continuous history. There are also lots of rock-cut tombs, tumuli and ancient remains that may be belonged to the villages of Pompeiopolis. Ancient city had been established by Pompeius on the main east-west road passes on Amnias valley, as a city state in the double province of Bithynia-Pontos in the year of 65/64 BC. After this time Pompeiopolis started to be developed and had been the metropolis of Paphlagonia in the period between the emperors Antoninus Pius and Gallienus. The city had been governed by Claudius Severus who was also the son-in-law of Marcus Aurelius in the second half of the 2nd Century AD., and he has been accepted as the Ktistes and the Patron of the city. The history of Pompeiopolis during the late Roman and early Byzantine periods is learned from the Bishop's Lists. It is known that the city had been evacuated in the late 6th or early 7th centuries AD., it is seen in the Bishop's Lists until the 14th century AD. Most probably people went on living in Kızkalesi and also Taşköprü.