These should really be made in to movies!  The favourite here is the story of the Prince of Poyais, but there are nine more that you might not believe.

Gregor MacGregor started out as a soldier of fortune in Latin America, at turns fighting both for and against the armies of Portugal and Spain in Central America and Florida. When he returned to Europe in 1820, MacGregor launched an audacious moneymaking scheme by announcing that while in the tropics he had been put in control of a small (and absolutely fictional) country he referred to as Poyais. He claimed the nation to be quite modern and friendly to Europeans and even produced hand-drawn maps and a copy of their constitution to back up his story. 

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