The Istanbul pogrom, also known as the Istanbul riots or September events (Greek: Σεπτεμβριανά Septemvriana, "Events of September"; Turkish: 6–7 Eylül Olayları, "Events of September 6–7"), was organized mobattacks directed primarily at Istanbul's Greek minority on 6–7 September 1955. The pogrom was orchestrated by the Turkish government under Prime Minister Adnan Menderes. The events were triggered by the false news that the Turkish consulate in Thessaloniki, in northern Greece—the house where Mustafa Kemal Atatürk had been born in 1881—had been bombed the day before. A bomb planted by a Turkish usher at the consulate, who was later arrested and confessed, incited the events. The Turkish press, almost fully under Menderes' control, conveying the news in Turkey, was silent about the arrest and instead insinuated that Greeks had set off the bomb.
A Turkish mob, most of which had been trucked into the city in advance, assaulted Istanbul’s Greek community for nine hours. Although the mob did not explicitly call for Greeks to be killed, over a dozen people died during or after the attacks as a result of beatings and arson. Armenians were also harmed.
The pogrom greatly accelerated emigration of ethnic Greeks from Turkey, and the Istanbul region in particular. The Greek population of Turkey declined from 119,822 persons in 1927, to about 7,000 in 1978. In Istanbul alone, the Greek population decreased from 65,108 to 49,081 between 1955 and 1960. The 2008 figures released by the Turkish Foreign Ministry place the current number of Turkish citizens of Greek descent at 3,000–4,000; however, according to Human Rights Watch, the Greek population in Turkey was estimated at 2,500 in 2006.
The Georgian community in Istanbul was also targeted. It is estimated that there were about 10,000 Catholic Georgian residents in Istanbul in 1955. Most of the Georgians emigrated to Australia, Canada, Europe and the United States following the pogrom. As of 1994, there were only about 200 Catholic Georgians and a handful of Jewish Georgian families left in Istanbul. 
Some see the attacks as a continuation of a process of Turkification that started with the decline of the Ottoman Empire, rather than being a contemporary, bilateral issue. To back this claim they adduce the fact that roughly 40% of the properties attacked belonged to other minorities. Historian Alfred-Maurice de Zayas has written that in his view, despite the small number of pogrom, the riots met the "intent to destroy in whole or in part" criterion of the Genocide Convention.