No, not the major league from the 19th century -- the minor league from the 20th century. 
Does anyone know why the American Association was dissolved after the 1997 season? The Triple-A realignment occurred in concert with the 1998 expansion which added the D'backs and Rays (and moved the Brewers to the NL) and which also added two Triple-A expansion teams (Durham and Memphis). While that explains the timing, it doesn't really explain the reason.
There had been three Triple-A minor leagues since 1969, when the American Association was revived (after it first folded in 1962 due to major league franchise shifts that took away its largest markets). As I understand it, the reason the AA was revived in 1969 was to reduce travel costs, since after 1962 the teams within the eastern International League and the western Pacific Coast League had to travel longer distances to play the former AA teams in the central US. What's confusing is that I've seen travel costs also listed as an explanation for the AA's dissolution in 1997. This doesn't make any sense, since the two surviving leagues both again had farther to travel, just like after 1962 (the PCL in particular, which picked up most of the AA teams after 1997 -- Nashville is pretty far from Vancouver).
Other contributing factors may have been the desire of the Buffalo Bisons to move from the AA to the IL, where the nearby Rochester and Syracuse teams played, and the (re)institution of the Triple-A World Series, which would have been difficult to do with three leagues instead of two (though the project failed miserably and was suspended after three seasons). However, to me, neither of these reasons seem to justify the Triple-A realignment after 1997.
As I see it, the most sensible course would have been to simply move Buffalo to the IL, Columbus and Toledo to the AA, and add Durham to the IL and Memphis to the AA. Then each of the three leagues would have had 10 teams, like so:
International League
North Division: Buffalo, Ottawa, Pawtucket, Rochester, Syracuse
South Division: Charlotte, Durham, Norfolk, Richmond, Scranton/Wilkes-Barre
American Association
North Division: Columbus, Indianapolis, Iowa, Omaha, Toledo
South Division: Louisville, Memphis, Nashville, New Orleans, Oklahoma
Pacific Coast League
North Division: Calgary, Edmonton, Salt Lake, Tacoma, Vancouver
South Division: Albuquerque, Colorado Springs, Fresno, Las Vegas, Tucson
So can anybody clue me in here?

Does anyone know why the American Association was dissolved after the 1997 season? The Triple-A realignment occurred in concert with the 1998 expansion which added the D'backs and Rays (and moved the Brewers to the NL) and which also added two Triple-A expansion teams (Durham and Memphis). While that explains the timing, it doesn't really explain the reason.
There had been three Triple-A minor leagues since 1969, when the American Association was revived (after it first folded in 1962 due to major league franchise shifts that took away its largest markets). As I understand it, the reason the AA was revived in 1969 was to reduce travel costs, since after 1962 the teams within the eastern International League and the western Pacific Coast League had to travel longer distances to play the former AA teams in the central US. What's confusing is that I've seen travel costs also listed as an explanation for the AA's dissolution in 1997. This doesn't make any sense, since the two surviving leagues both again had farther to travel, just like after 1962 (the PCL in particular, which picked up most of the AA teams after 1997 -- Nashville is pretty far from Vancouver).
Other contributing factors may have been the desire of the Buffalo Bisons to move from the AA to the IL, where the nearby Rochester and Syracuse teams played, and the (re)institution of the Triple-A World Series, which would have been difficult to do with three leagues instead of two (though the project failed miserably and was suspended after three seasons). However, to me, neither of these reasons seem to justify the Triple-A realignment after 1997.
As I see it, the most sensible course would have been to simply move Buffalo to the IL, Columbus and Toledo to the AA, and add Durham to the IL and Memphis to the AA. Then each of the three leagues would have had 10 teams, like so:
International League
North Division: Buffalo, Ottawa, Pawtucket, Rochester, Syracuse
South Division: Charlotte, Durham, Norfolk, Richmond, Scranton/Wilkes-Barre
American Association
North Division: Columbus, Indianapolis, Iowa, Omaha, Toledo
South Division: Louisville, Memphis, Nashville, New Orleans, Oklahoma
Pacific Coast League
North Division: Calgary, Edmonton, Salt Lake, Tacoma, Vancouver
South Division: Albuquerque, Colorado Springs, Fresno, Las Vegas, Tucson
So can anybody clue me in here?
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