New York's official nickname is the "Empire State." While some theories claim George Washington gave the state this nickname, notably due to its key role in the country's economy, there is no confirmed reason on how New York earned this name.
The Empire State's economy, and that of all the United States, suffered severely in the crash of 1929. As part of the effort to reassert the economy and New York's role as a producer, construction of the Empire State Building began in 1930 (with plans only a few weeks old) and was finished in 1931.
The building was the tallest in the world until 1972 (now 23rd) and remains a cultural marker for New York City.