The National Baseball Hall of Fame was dedicated in 1939 at Cooperstown, New York, to honor the centennial of the alleged invention of baseball by Army officer Abner Doubleday at Cooperstown in 1839.
However, it was later proven that Doubleday was not even at Cooperstown in 1839 (he was a cadet at West Point) and that the word “baseball” was used as early as the 18th century to refer to American and British ancestors of the modern game.
Credit for the codification of modern baseball rules now usually goes to Alexander Cartwright and the Knickerbocker Club of New York in 1845.