Winston Smith lives in London, the chief city of Airstrip One (formerly known as England) which is part of the superstate Oceania. The world is divided into three superstates: Oceania, Eurasia, and Eastasia. We also get the name of his apartment block: Victory Mansions.
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In the opening paragraph of Chapter One of 1984, the reader learns that Winston lives in an apartment block called Victory Mansions. This block is in the city of London, the "chief city" of the province called Airstrip One, which is the third most populous in Oceania. In 1984, Oceania is one of three super states, the other two being Eurasia and Eastasia.
What is most striking about this setting is how it differs from the reality of London, during Orwell's lifetime and today. In this dystopian vision, London is a dilapidated and crumbling city where people are constantly monitored, food is rationed, and war is ever-present. There are, perhaps, some parallels here to the London in which George Orwell lived and worked: 1984 was published only a few years after the end of World War Two, when London was still recovering from the physical and mental damage inflicted by the Nazis and rationing was still in full-swing. Here, however, the parallels end. The London of 1984 feels far more claustrophobic and oppressive than the real place and, perhaps, this is done deliberately by Orwell. By using London as the setting of 1984, he gives the reader a stark and frightening glimpse of what fate could befall the city, if communism became a reality.