Charles Ponzi was an Italian-American con artist and swindler who became infamous for his fraudulent investment scheme in the early 1920s. He is best known for his 'Ponzi Scheme', which promised investors a 50% return on their investments within 45 days. The scheme was based on the idea of using money from new investors to pay off earlier investors, creating the illusion of a successful business. Charles Ponzi was eventually arrested and sentenced to five years in prison for fraud.