The National Pastime

While baseball is known as the National Pastime, it's origins are generally traced to various forms of informal stick and ball games that have been played for centuries.

The most direct link to what would become American baseball is probably the English game of rounders (pictured below).

The man and group that receive credit for modifying the game with rules that we would certainly recognize today are Alexander Cartwright and the NY Knickerbocker Club (pictured at bottom). Click on this link for a good explanation of the early evolution of baseball in America. (Cartwright is the gentleman in the top/middle).