How did reggae music originate?

Reggae formed when Ska and Rocksteady bands started to experiment with slower tempos and stripped down arrangements in the mid/late 60's. Ska was the result of imported pop records from the US and Europe. Often only a few copies of the 'original' made it to Jamaica, so enterprising bands and producers would record cover versions and release them.

The origin of the term 'reggae' is disputed, the most popular story is of Toot Hibbert who was joking with friends and said "lets do the reggay" and wrote the song "Do the Reggay" in 1968.