Reggae's development in Jamaica has much in common with the rise of post-war jazz, and it parallels the surge of R&B in the U.S. Under British rule until 1962, Jamaicans in the '50s were increasingly conscious of American music when large sound systems and turntables became a staple of social gatherings.
In the years before Jamaica's famed record studios were in place, neighborhood yard-party disc jockeys relied on laborer-friends to bring singles home from the States after they finished working on American farms during harvest season. Musicians eventually recorded covers of these songs after Jamaica's independence, and you can hear the influence of prolific American R&B artists such as Fats Domino and Louis Jordan in early ska beats.
That's enough to get you started. Now go make some coffee (or popcorn, if you're reading this in the evening). Here's a three-part BBC documentary on reggae's glorious history...

