Blue Beat definitely came first, There was a tune called 'O Carolina' which I think was made into a pop record a few years back. That was the first tune I remember, I think it was sung by a band called 'Prince Busters All Stars'. The name changed from Blue Beat to Ska then to Rock Steady then Reggae. If you walked through Brixton SE London in the mid sixties there were BIG sound systems blasting out tunes everywhere