On the origin of the hip/hipness/hippie terminology:
Sorry I don’t have the reference with me at the moment, some friend has run off with my copy of the book - Bill Bryson, in Made in America, has a chapter on the contributions made to American english by African migration and the slave trade, a contribution which has been sadly underrated for some time. One item he notes is the west African term “hepikat”, meaning one who has his eyes open, or is very in tune with his surroundings. This morphed to hipcat, which was shortened to hip, then modified to hippie. Apparently the transition is fairly well documented.
Mind you, this has absolutely nothing to do with the “hip hip hooray” business.
The word Detective tells it a little differently, but still mentions a link to an african term - but also stating that there are some linguistic problems with the link.
Bryson is an extremely entertaining writer, a wonderful stylist and a great yarn-spinning raconteur. But a researcher, he ain’t. I’ve read most everything he’s written, but I keep the salt handy.