As someone who did most of his growing up in the 1960s, I like to believe that I know my oldies. I do well with naming 1960s pop and rock hits, the artists and release years (and sometimes even season of the year).
And while I know some trivia about the major artists -- Elton John's name is really Reginald Dwight, etc. -- those facts are not my strongest suit.
Still, I was surprised, after buying a British Invasion compilation, The British Are Coming Vol. I, to discover that several of the bands on the CD were British. Can't say that I thought about it much, but I assumed they were American. For 40 years or so, I didn't realize the acts were also part of the Invasion.
Sure, I knew the Kinks and the Searchers and Donovan were all British. Even the Tremeloes.
But Mungo Jerry, whose one hit was "In the Summertime"? And the Foundations? And how about Status Quo with their psychedelic "Pictures of Matchstick Men"? Now they sound American. Don't they?
What is it that caution about assumptions?