Tammany Hall was the Democratic Party political machine that played a major role in controlling New York City politics and helping immigrants (most notably the Irish) rise up in American politics from the 1790s to the 1960s. It usually controlled Democratic Party nominations and patronage in Manhattan from the mayoral victory of Fernando Wood in 1854 up to (but not including) the election of Fiorello La Guardia in 1934, whereupon it weakened and collapsed.
Benson John Lossing, ed. Harper's Encyclopedia of United States History (vol. 9) (New York, NY: Harper and Brothers, 1912)
Courtesy the private collection of Roy Winkelman