William Magear Tweed (April 3, 1823 April 12, 1878) – often erroneously referred to as "William Marcy Tweed" (see below), and widely known as "Boss" Tweed – was an American politician most notable for being the "boss" of Tammany Hall, the Democratic Party political machine that played a major role in the politics of 19th century New York City and State. At the height of his influence, Tweed was the third-largest landowner in New York City, a director of the Erie Railroad, the Tenth National Bank, and the New-York Printing Company, as well as proprietor of the Metropolitan Hotel.
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