Perhaps, such whimsical words were there for the purpose to make his readers understand that a whole context of a book should not be taken too literally... unlike a regular Bible is perceived literally. (there was this spy movie where a spy explains that very last information - usually stays in mind) Now, why exactly this song with the words: "rose"... oh, well, because its a queen of flowers, and why "yankee", or because its "american" and blah-blah-blah... maybe he liked the song
Yankee Rose was one of the standard organ tunes he'd play at gigs. I think he just liked the song. I doubt it had much meaning beyond that. The 2 words would be speculated on as if they were "Rosebud" from Citizen Kane. It probably was a playful touch on his part. I'm sure he knew it could have the odd effect it did. It really never was a secret though. Coming across the sheet music reminded me that folks still asked about "Yankee Rose"
Mr. Emmanuel: you live in the heart of Yorubaland. Yoruba magic and religion had an enormous impact on Cuban and Brazilian spirituality and a lesser but still huge impact on Haitian Vodou. Why not share with us some stories about the Ifa traditions and about Nigerian folk practices? Once you've provided some information about Witchcraft, the Second World, etc. I'm sure you'll find people on here will be more willing to help you.
Kudos to Dr. Aquino and Zeena Schreck for solving the "Yankee Rose" mystery. Zeena's explanation is credible, fits the known facts and answers the question better than any other theory proffered to date. When you're writing Anton LaVey's biography that's generally as good as it gets.
Initially, I considered it like the final period at the end of his manifesto. Much like he had a disdain for Thelemites discussing Liber Al vel Legis (and the Thelemites), he figured Satanists would end up in a perpetual state of Wax Philosophical as to its meaning. Much like Crowley added 'The Comment', he finished it off with 'Yankee Rose'.
I don't really care what it means, or was intended to mean according to the Super-sleuths. It's quite irrelevant to me, mine and so forth.
I personally think it could be related to his music or something he witnessed in his younger years, maybe a nickname for a lost love. Though it could also be a crude inside joke that no one would ever understand. There's another possibility that it could be completely meaningless or the meaning could go deeper than we seem to think. The scientific name for Rose would be Genus Rosa, the root of genus being 'Gen' meaning 'race and kind of' and Yankee meaning 'from the northern states'. If you simply put these definitions together not much sense comes from it but if you think more of it then you see that he could've been referring to a certain type of rose that only grows in a certain northern state. Whatever it may be "Yankee Rose" certainly is a mystery that may never be understood entirely.