This map was made in 1870 during a time of great change for the New York City parks. A group of corrupt politicians, known as the Tweed Ring after William “Boss” Tweed, abruptly replaced the Board of Commissioners of Central Park with a new city agency, the Department of Public Parks. The new parks commissioner, Peter B. Sweeny, then fired designer of Central Park Frederick Law Olmsted, Calvert Vaux, and Andrew Haswell Green, the park comptroller. Tweed and Sweeny, along with the other key ring members, Mayor Abraham Oakey Hall and Comptroller Richard B. Connolly, seized control of the finances of the city and embezzled hundreds of millions of dollars. The Tweed Ring was exposed in 1871 and the Department of Public Parks was taken over by some of the former commissioners of Central Park. Andrew Haswell Green was reinstated as Parks Department comptroller, and Olmsted and Vaux were rehired. The new Department of Public Parks completed Central Park and relandscaped many other Manhattan parks in the early 1870s, including Madison Square, Washington Square, Union Square, and Tompkins Square.