I'm fairly certain that Swing developed along with the big-band sound of the 20's. All dance traditions take pieces from other things that have gone before, but swing is an American development.
I found the following information on the Metronome Ballroom's (
www.metronomeballroom.com) website a year ago, but I can't locate the specific page again now.
"East & West Coast Swing
The origins of these two popular swing dances go all the way back to the swinging Savoy Ballroom, which opened in Harlem in 1926. With a dance floor that was a block long and a raised stage, the Savoy attracted some of the best bands and dancers in the world during its 32 year history. According to one scholar, the swing dance called the Lindy Hop first saw the light of day at the Savoy. The Lindy was named after Charles Lindbergh, who had become a household name after his solo flight across the Atlantic. This partner dance was characterized by a "breakaway" or solo part, said to have been invented by "Shorty George" Snowden, which allowed the male dancer in particular to strut his stuff. The dance's acrobatic and airborne steps may have caused the association with Lindbergh and his historic flight.
The Lindy was performed mostly by small groups of enthusiasts. But by 1936, it had been refashioned as the Jitterbug, capturing the imagination of young people everywhere. Benny Goodman, the "King of Swing," brought dancers out in droves. Jitterbugging was athletic and vigorous, and it was widely danced to swing music until about the end of World War II. But many people thought jitterbugging was too violent to fit in as a ballroom dance. Accordingly, it was tamed by professional dancers and turned into Jive. The Jive was danced in clubs in the 1950s and is now one of the five standard Latin dances in ballroom competitions. The history of the other modern swing dances is fuzzy; apparently no historian has fully researched their origins. All we know for sure is that East Coast and West Coast Swing both evolved out of earlier versions of Swing. Noted Los Angeles dance teacher Skippy Blair offers one possible explanation: "In the early 40s everything was Jitterbug, but then it got so wild that even drinking patrons were getting hit by dancers. There are several sources that say that west coast came from that: They drew lines on the ground and said you couldn't move out of those lines."
West Coast Swing is danced in a slot and is noted for its syncopated steps. Followers have more freedom than perhaps in any other dance, performing their own syncopations at will. West Coast Swing became the official state dance of California in 1988. East Coast Swing is distinguished by its rock step. Its name was changed from Eastern Swing to East Coast Swing between 1975 and 1980, according to Blair, years after "western" swing had become known as "West Coast" Swing. East Coast Swing was originally danced to big band music. Regional music differences helped determine how the two dances evolved. "Back east they stayed with the big band sound, which you could only do eastern swing to. But here, we didn't have big band places; we had country-western and blues. Dancing in a slot (i.e., West Coast Swing) fit that kind of music better," Blair says."