Under John VIII the territory of the Empire was reduced to the most modest extent. Shortly before his father's death John had been forced to cede several cities of Thrace to the sultan. After John had become sole ruler of the Empire, his power extended, properly speaking, over Constantinople and the nearest surrounding country. But the rest of the Empire, for example, the Peloponnesus, Thessalonica, and some scattered cities in Thrace, were under the power of his brothers as separate principalities almost entirely independent.
In 1430, Thessalonica was conquered by the Turks. One of the brothers of John VIII, who was governing Thessalonica with the title of despot, realized that with his own forces he could not contend with the Turks, and sold the city to Venice for a sum of money. Venice in taking possession of this important commercial point pledged herself, according to Ducas, to protect and nourish it, raise its prosperity, and make it a second Venice. But the Turks, who already possessed the surrounding country, could not tolerate the establishment of Venice at Thessalonica. Under the personal leadership of the sultan, they laid siege to Thessalonica; the course and result of the siege are well described in a special work, On the last capture of Thessalonica, written by a contemporary, John Anagnostes (i.e., Reader). The Latin garrison of Thessalonica was small and the population of the city regarded the new Venetian masters as aliens. They could not resist the Turks who, after a short siege, took the city by storm and exposed it to terrible destruction and outrage. The people were murdered without distinction of sex or age. Churches were turned into mosques, but the Church of St. Demetrius of Thessalonica, the chief patron of the city, was temporarily left to the Christians, though in a state of complete desolation.
A History of the Byzantine Empire - Table of Contents
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