And then there was one

INDIANAPOLIS, INDIANA - The National League was the only "major" league left standing on this date in 1891 when the American Association folded. The National League announced at its winter meetings in Indianapolis that four AA teams, the Baltimore Orioles (today's New York Yankees), St. Louis Browns (today's Baltimore Orioles), Louisville Colonels (defunct) and Washington Senators (today's Minnesota Twins)would be absorbed by the NL making it a 12-team league.

Several other American Association teams had been absorbed by the NL in previous years; the Pittsburgh Alleghenys (todays Pirates), Cleveland Spiders (defunct), Cincinnati Red Stockings (today's Reds) and Brooklyn Bridegrooms (today's Los Angeles Dodgers).

The American Association had challenged the National League as a second major league from 1882 to 1891. The two leagues even had seven World Series during those years. While the American Association wasn't viable enough to survive, the National League must have felt threatened by it, since it eventually absorbed several teams.

The National League's monopoly of major league baseball didn't last long. In 1900 the NL dropped the four American Association franchises absorbed in 1891. The Baltimore Orioles, St. Louis Browns and Washington Senators became members of the new American League. The Louisville Colonels folded as a major league team. The Colonels surfaced again as a minor league team in the American Association which existed from 1902 to 1962 and 1969 to 1997, but it was not connected to the original AA.

Contributing sources:
The Associated Press (AP), Indianapolis, Indiana, December 17, 2008
American Association Timeline
Baseball-Reference 

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