The British Invasion was an exciting musical event.
I can remember hearing "My Generation" (The Who) on the radio and immediately pestering my folks to buy me a Fender bass.(John Entwhistle played the first bass solo on a top 40 hit).
I see a lot of people getting the British Invasion acts wrong. No, Pink Floyd isn't B.I. Yes, the Searchers are
I think the main factor that fueled the invasion was the fact that British teenagers fell in love with American R&B and Blues. Even the Beatles played nothing but ,in their Cavern Club days.
The first few Stones albums had a ton of Willie Dixon, Chuck Berry, Larry Williams, Marvin Gaye, Sam Cooke,etc.
The Animals scored a huge hit with an old American folk song, "The House Of The Rising Sun"
Some bands and artists that are sometimes omitted from the B.I. list:
~Them with Van Morrison
~The Nashville Teens
~Peter & Gordon
~Chad & Jeremy
~Gerry & The Pacemakers
~Freddie & The Dreamers
Here's a fine article that has a rather sterile and long title:The Pendulum of Cultural Imperialism: Popular Music Interchanges Between the United States and Britain, 1943–1967
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