mid-third c.: Occupation of Tyras by the Goths. Possible gradual decline and abandonment of the city.
mid-tenth c.: Asprokastron is mentioned for the first time in Byzantine sources.
c. 1060-1064: Possible date of the creation of a bishopric in the region.
early thirteenth c.: Asprokastron passes under Cuman control.
mid-thirteenth c.: Asprokastron passes under the control of the Tatars of the Golden Horde.
second half of thirteenth c.: A Genoese trading port is founded in the region.
1330: Traditional date for the martyrdom of St John the New in Asprokastron.
mid-fourteenth c.: Asprokastron passes under Genoese control.
end of fourteenth or beginning of fifteenth c.: Asprokastron is annexed to the newly-founded principality of Moldavia.
1420: Unsuccessful Ottoman attempt to capture the city.
1437: A Venetian trading post is founded in the city.
1439: Byzantine emperor John VIII Palaiologos passes through the city en route to Constantinople.
after 1453: Possible transportation of part of Asprokastron’s inhabitants to Constantinople by sultan Mehmet II.
1457: Asprokastron becomes the seat of the Moldavian prince Stephen the Great.
5 August 1484: The city is captured by the Ottomans.