Origins of Modern American Sport

The first truly significant sports event in American history is generally accepted to have been a horse race.

In 1823, a two of three heats (each heat lasting 4 miles!) match race between Sir Henry and American Eclipse took place on Long Island in front of 60,000 spectators.

The race (won by American Eclipse in three heats) not only marked the rise of popular spectator sports in the U.S., but also the growing regional tensions between North and South in the young nation. The link above provides a concise summary of the race (along with good links to horse racing information), while this article provides a nice overview of the sport's history.

American Eclipse