Wikipedia - J3 League

J3 League (Japanese: J3リーグ, Hepburn: J3 Rīgu) or simply J3 is the third division of Japan Professional Football League (日本プロサッカーリーグ, Nihon Puro Sakkā Rīgu). It was established in 2013 as the third-tier professional association football league in Japan under the organization of J.League. The league is known as the Meiji Yasuda J3 League (Japanese: 明治安田J3リーグ) for their title sponsor.

The third-tier nationwide league is a relatively recent development in Japanese football with a first attempt made in 1992 (second division of the old JFL), though it only lasted for two seasons. In 1999, following the establishment of J2 League, a new Japan Football League was created to comprise the third tier and lower divisions. After the introduction of J3, the JFL was demoted to the fourth-tier nationwide league, for the first time in history of Japanese football.