The town was founded as a colony from the Greek city of Miletus Miletus in the 7th century BC. According to Strabo, the town was only remarkable as the birthplace of Philetaerus, founder of the royal dynasty of Pergamon.
At the beginning of the 3rd century BC, together with Cromna, Cytorus, and Sesamus, Tium was incorporated with the new city of Amastris. Of the four towns, Tium alone, probably in 282 BC, recovered its autonomous status.
Tium was part of Bithynia, which on the death of King Nicomedes IV in 74 BC became a Roman province. Emperor Theodosius I (379–392) incorporated it into Honorias, when he carved out this new province from portions of Bithynia and Paphlagonia and named it after his younger son Honorius. In 535, the Emperor Justinian united Honorias with Paphlagonia in a decree that expressly mentioned Tium among the cities that were affected.
Le Quien (Oriens christianus, I, 575) mentions among its bishops:
- Apragmonius at the First Council of Ephesus in 431;
- Andrew in 518;
- Eugenius in 536;
- Longinus at the Sixth General Council in 681;
- Michael at the Seventh General Council in 787;
- Constantine, at the Eighth General Council in 869, and author of an account of the transfer of the relics of St. Euphemia of Chalcedon (Acta Sanctorum, September, V, 274-83).
This see figures in all the Notitiae episcopatuum.
- Ancient coinage of Bithynia
- William Smith, A Dictionary of Greek and Roman Biography and Mythology, "Leocritus"
- William Anderson, "Late Byzantine occupation of the castle at Tios" in Anatolia Antiqua XVII (2009), pp. 265-277
- Miletos, the ornament of Ionia: a history of the city to 400 B.C.E. By Vanessa B. Gorman Page 70 ISBN 0-472-11199-X
- Strabo, Geography 5.3.8
- Novella 29 of Justinian
- Michel Lequien, Oriens christianus in quatuor Patriarchatus digestus, Paris 1740, Tomus I, coll. 575-576]