P. T. Barnum - The Greatest Showman on Earth is a biography of Phineas Taylor Barnum who is most famous for founding the Ringling Bros. and Barnum & Bailey Circus, one of America's best known circuses. Barnum was a successful self-made businessman and showman who became famous for his exhibitions of human and animal oddities. P. T. Barnum - The Greatest Showman on Earth is highly recommended for those interested in the history and life of P. T. Barnum, American showman and entrepreneur.