As far as I’m aware, Castaneda was the first person in the popular culture to discuss lucid dreaming, in his 1972 book Journey to Ixtlan. And his associate/groupie Taisha Abelar wrote an article about “Tibetan Dreaming” in an obscure journal in 1970.
Castaneda was obviously doing lucid dreaming well back into the Sixties.
He was a notorious liar and a cult leader, but did he have anything to say about lucid dreaming that was worth listening to?
Yes, he did, in his 1993 book The Art of Dreaming. I highly recommend it, although you need to skip all the stuff about the assemblage point, Don Juan and the Tenant.
He was a wonderful author too… I read most of his books in two or three sittings – his writing style really sucks you in. Whether he was the “first” or not is up for debate, since people have been doing this stuff for a long, long time – but he definitely helped to popularize it.
It’s like an alternative theory as to what dreams are – it may be entirely wrong, or maybe pieces of it are wrong, or maybe it’s entirely true… It’s worth giving due consideration, however. Kinda a shame the Conquistadors burnt all those books, though…