X League

The X League is Japan's top American football organization. It was founded in 1971 and is made up of 55 teams divided into three tiers: X1 Super, X2, and X3. The top tier, X1 Super, has eight teams that stretch geographically from the Kanto to Kansai regions.

X League players are all amateurs. Teams may include up to four import players from overseas, with no more than two allowed on the field at a time.

The X League season runs from spring to autumn, with the championship game, the Rice Bowl, being held in December.