When the Germans over-ran western Europe in summer 1940, the Americans took over the defense of a bunch of British possessions in the Americas: in the Bahamas, Guyana, the Leeward Islands, and southern Jamaica. Lonely American kids far from home brought American music with them. Later on, radio stations of the Armed Forces Network played American music all over the world. People with radios listened to that music. It wasn’t Lawrence Welk. In the Caribbean, people could hear both jazz and rhythm and blues.
Traditionally, Jamaicans had listened to live music, usually in dance-halls. After the Second World War, radio DJs and music promoters began running what were called “sound systems.” These were flat-bed trucks with generators, big speakers, and turntables. The idea was to roll into some poor neighborhood, begin blasting music, draw a crowd, and sell goat-jerky and white lightning to the audience. This innovative approach to marketing soon won large audiences. The trouble was that it threatened to put the owners of dance-halls out of business. How to regain market share? They started hiring “rude boys” to go cause a ruckus at “sound system” street dances. Cut somebody’s face with a straight-razor, stuff like that. This made the dance halls seem somehow…safer. How were the “sound system” promoters going to regain market share? They hired their own “rude boys.” Rinse and repeat. So, Jamaican music started to acquire a certain association in some minds—those of the venue-owners, the performers, the audience, the “rude boys” themselves–with violence.
Then the Americans moved on to rock and roll, leaving R and B behind. Jamaicans didn’t like rock and roll as much as they liked R and B, so the “sound systems” started paying for original local music to record and play. “Duke” Reid opened the first Jamaican studio in 1959.
There is an interesting progression in Jamaican music. Mento is a kind of Jamaican folk music that developed in the 1940s and became very popular in the 1950s. It sounds like calypso to my ignorant ear, but purists insist there is a difference. Mento emerged as dance-hall music that was popular with poor people. Hence, Marcus Brewer’s analysis of rap music applies to mento. Ska then added influences from American jazz and rhythm and blues in the late 1950s. It replaced mento (without destroying it). It also spread to Britain, where it became popular with “mods” and later with “skinheads.” Rocksteady then emerged about 1966 as a slowed-down version of ska. By mid-1968 music had moved on yet again to reggae. Part of the explanation for this is the growing influence of Memphis and Detroit “soul” music. (See: Motown, Stax, and Atlantic Records.) Reggae emerged from this line of succession in the late 1960s.
What’s distinctive about reggae? It’s the mood as much as anything else (I would argue). Partly, this comes from the emphasis on suffering and hardship in the wake of the failed hopes of the early Sixties. Partly, the simple chord progressions or—according to my technical advisor–smoking a lot of ganja encourage a meditative mood. Partly, many of its musicians and followers were Rastafaris whose faith explained past suffering and promised future redemption.
How did reggae get to the United States? The character “Pussy Galore” in Ian Fleming’s James Bond novel was modeled on Blanche Lindo. Her son, Chris Blackwell (1959- ) founded Island Records in Jamaica in 1958, then moved it to Britain in 1962. Here he promoted Jamaican music for a British audience. He produced the movie “The Harder They Come” (1972) and the first Bob Marley and the Wailers album outside Jamaica “Catch a Fire” (1973). Eric Clapton covered “I Shot the Sheriff” (1974), introducing Marley to a huge American audience. The Wailers toured the US with Johnny Nash (1974), but got fired for being much more popular.
 “They’re pretty angry most of the time, but sometimes they just want to have sex.”–“About A Boy” (2002).