Western League (NPB)
The league was created in 1952 as the Kansai Farm League, and contained the minor league teams of the seven professional teams that had their homefields in the western region of Japan. The original teams in the league were, the Osaka Tigers, Hankyu Braves, Nankai Hawks, Nagoya Dragons, Nishitetsu Lions, Shochiku Robins, and Sanyo Crowns. The league was initially completely separate from the workings of the NPB. The Sanyo Crowns were dissolved in 1952, and the Shochiku Robins merged with the Taiyo Whales in 1953, to cut the number of teams down to five. The Kintetsu Pearls joined in 1953, but the six teams of the Central League decided to form their own minor league in 1954, and the Chunichi Dragons and Hanshin Tigers dropped out of the league to leave only four teams in the league.
The league decided to join the NPB in 1955, and the 14 minor league teams of the Central League and Pacific League were split up to create the Western League and Eastern League. The new league consisted of the minor league teams of, the Hanshin Tigers, Hankyu Braves, Nankai Hawks, Chunichi Dragons, Nishitetsu Lions, Kintetsu Pearls, and Hiroshima Carp. The Lions moved their franchise to Saitama in 1979 to join the Eastern League, and the Orix BlueWave and Osaka Kintetsu Buffaloes merged to become the Orix Buffaloes in 2005, leaving five teams in the league.
The Hiroshima Carp minor league affiliate was called the Hiroshima Greens, or Hiroshima Carp Greeners, before returning to their parent team's name in 1958. The same goes for the Hanshin Tigers minor league team, which was called the Hanshin Jaguars until 1957. The Orix BlueWave minor league team became Surpass Kobe in 2000, and the Orix Buffaloes minor league team is currently named Surpass.
The league contains the minor league affiliates of five Japanese professional teams (minor league homefield shown in parentheses):
- Chunichi Dragons (Nagoya, Aichi)
- Hanshin Tigers (Nishinomiya, Hyogo)
- Orix Buffaloes (Kobe, Hyogo)
- Hiroshima Toyo Carp (Iwakuni, Yamaguchi)
- Fukuoka SoftBank Hawks (Fukuoka, Fukuoka)
Most of the Japanese minor league teams carry the same name, and use the same uniforms as their parent team, with the exception of the Yokohama BayStars (Shonan Searex), Orix Buffaloes (Surpass), and Saitama Seibu Lions (depends on the sponsored company, but currently using Saitama Seibu Lions) minor league teams.