Who is William "Boss" Tweed from Reconstruction: America's Unfinished Revolution, 1863-1877 and what is their importance?

William "Boss" Tweed was a New York City political operator. Over the years, he defrauded the city of millions of dollars, directing some of those funds to assist immigrant families. Tweed controlled the appointment and elections of city officials until he was charged and tried for forgery and larceny. Tweed was convicted of those crimed in 1873. Samuel Tilden, the prosecutor in Tweed's trial, later ran for president.