Great Thessaloniki Fire of 1917

The Great Thessaloniki Fire of 1917 (Greek: Μεγάλη Πυρκαγιά της Θεσσαλονίκης, 1917) destroyed two thirds of the city of Thessaloniki, the second-largest city in Greece, leaving more than 70,000 homeless. The fire burned for 32 hours and destroyed 9,500 houses within an extent of 1 square kilometer. Half the Jewish population emigrated from the city as their livelihoods were gone. Rather than quickly rebuilding, the government commissioned the French architect Ernest Hébrard to design a new urban plan for the burned areas Thessaloniki and for the future expansion of the city. His designs are still evident in the city, most notably Aristotelous Square, although some of his most grandiose plans were never completed due to a lack of funds.

Thessaloniki was one of the largest and most modern cities in Europe by Balkan standards at the time of the fire. By European standards, the city's planning was chaotic and the unhygienic conditions that prevailed in the poorer areas were described as "unacceptable" by the government in Athens. The city's harbour was one of the most important centres of trade in the region. In 1912 the city, along with the biggest part of Macedonia and Epirus, was incorporated in Greece. The population of the city was essentially maintained: the larger part of the population were Sephardi Jews, followed by Greeks, Turks, Bulgarians, Roma and others.

As soon as World War I began in 1914, Greece officially maintained neutrality. With authorization by the Venizelos' government, Entente Forces had landed troops in Thessaloniki in 1915, in order to support their Serb allies in the Macedonian Front. In August 1916, Venizelist officers launched an uprising that resulted in the establishment of the Provisional Government of National Defence in the city, essentially dividing Greece into two sovereign states, one represented by Eleftherios Venizelos, and the other by King Constantine. After King Constantine abdicated in June 1917, Greece was reunified again and entered officially the war with the Allies side.

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