Thessaloniki was a part of the Byzantine empire for as long as there was an empire, since it belonged to it from 379 A.D. until 1423 (with the exception of the fall of the whole empire in
1204 to the forth crusade until 1246) when it was sold for seven years to Venice before becoming yet another capture of the ottoman empire. Thessaloniki was only second to Constantinople in importance to the empire and had a lot of power. Even today we can see Thessaloniki’s Byzantine past all over the city with its many Paleochristian and Byzantine monuments that even belong to the UNESCO world heritage. And like her byzantine past inspire us today, they were two brothers back then that inspired all the Slavs.
Saints Cyril and Methodius were born in Thessaloniki in the early 9th century and in 862 they began their most important mission. When Prince Rastislav asked for missionaries to evangelize his people from the Byzantine empire, the emperor turned to Cyril and his brother to follow with the task. One of the first things they did was the translation of the Bible in Old Church Slavonic. But to do that they accomplished their most important achievement which was the creation of the Glagolitic and Cyrillic alphabet, the second of which is still used in Slavic languages today. Finally one lesser, perhaps, achievement was the writing of the first slavic Civil Code of Great Moravia.
As mentioned before Thessaloniki forcefully became a part of the ottoman empire when in 1430 sultan Murad II defeated Venice (Thessaloniki was previously captured by the ottomans from 1387 to 1402 before they were forced to return in to the Byzantine empire). She was open to many religions as many times muslims and jews where more that the christian orthodoxs. During the 19th century the bulgarian element was strong in the city as well. The city flourished becoming one of the most important of the empire with growing trade routes and an important commercial center of the Balkans. But the city might have been more important to the ottomans that anyone could have imagined.
In 1881 in Apostoloy Pavlou Street (now) an important, maybe the
most important, figure for the future of the ottoman empire was born in Thessaloniki. He was Mustafa Kemal, a politician who shaped modern Turkey with his reforms. Also, a very important movement that aid to change the status of the empire to a country, the one of the Young Turks, was very active in the city.