Boss Tweed, whose real name was William Magear Tweed, was a notorious political figure in the United States during the 19th century, best known for his role as the leader of Tammany Hall in New York City. He exemplified the rampant political corruption of the era, using his position to gain immense wealth and power through bribery, kickbacks, and fraud, significantly influencing local government and politics. His influence and methods brought attention to the need for political reform as citizens began to demand accountability and transparency in governance.