Sport: Baseball

Formed: July 26, 1938Status: Active First Games: May 2, 1939 Seasons: 87 (as of 2026)States & Provinces: CA, MT, OR, UT, WA, AL, BC   Pioneer

Formed: January 22, 1888 Status: Active Level: Double-A First Games: April 1, 1888 Seasons: 131 (as of 2026) States: AR, KS, MO, NM, LA, MS, OK,

Formed:  December 10, 1902 Status: Active First Games: March 26, 1903 (San Francisco Seals @ Portland Beavers, Oakland Oaks @ Sacramento Senators, Seattle Indians @ Los

Formed: November 28, 1955 – The Mississippi-Ohio Valley League re-brands as the Midwest League First Game: April 29, 1956 Seasons: 70 & Counting (as of 2026)

Formed: Disbanded: October 16, 2019 (Merged with and became part of the Frontier League) First Game: Final Game: September 14, 2019 Seasons: 15 States &