Japan has had a long history from reggae in the country, dating all the way back to the mid to late 70s. All started when Bob Marley, one of the most recognized figures of reggae has came to Japan.
Dancehall has made such an impact in Japan, that the first foreign Dancehall Queen of Jamaica was in fact Japanese. Yes, Junko Kudo also known as Junko Bashment or Dancehall Queen Junko was the Dancehall Queen of Jamaica back in 2002, but has since lost her title.
Japan has since made their own Dancehall Queen competitions as seen in the video below.
Japanese reggae is an interesting mixture of Japanese, English and Jamaican patois (such as dem, gyal).
More Artists to look up:
And getting down to the nitty-gritty of the movement, we can't forget the fashion.
source: 1, 2, 3, 4, 4, 5, 6, 7, 8