Just to be devils advocate here for a second, I have no idea what it means either. The official 'Church of Satan' stance is that he wished the meaning kept secret, and aside from that my best guess is that it had something to do with the song of the same name he (reportedly) often closed his sets with.
Aside from that it has been reported that 'yankee rose' was some sort of ghost ship, but that's all rather vague too.
I'm not even sure if the phrase has any significance at all.
I have always thought that The "Yankee Rose" at the end of the SB had a connection to the way he reportedly closed his sets as well- that maybe LaVey likened creating the concept and writing the book to a non-musical performance, and the "Yankee Rose" was just his ironic way of "Closing the Set"
Also, the fact that people are still guessing about those two words over four decades after he wrote the SB, would no doubt be an immense source of amusement to LaVey if he was still with us today.
Maybe it was a personal experiment to see if the masses could be "confounded and confused" by an external source with almost no effort required- In The Doc's case, two well placed words in a book, with no accompanying explanation did that easily....
It could only have assisted in fueling his enthusiasm for further practical application in Lesser Magic, whatever his original reasons were for placing the words there.
To echo Jake, that secret has indeed been out of the bag for years. You just have to spend more than 3 minutes searching wiki. Also, I swear there was a thread about this topic here already. Must have been v1 or v2. Maybe someone with longterm memory can answer that. I know this topic was covered previously.
_________________________ Beer, the reason I get up every afternoon.
It is the answer to the question, What are the last two words on page 272 in your Satanic Bible?
That was one of the questions that I had to answer when I first joined this site... I remember trying to join at work then having to wait to get home only to see the answer was Yankee Rose... I think that was V2 (the last one)...
That and the title probation for the first 50 posts made you want to keep questions such as these in 101 where they belong...
"Are you ready for the new sensation?"
We are the music makers, And we are the dreamers of dreams. ~Arthur William Edgar O'Shaughnessy
Let's see... Yankee Rose comes at the end of TSB, and is a melodic tune. One deduction is: We know that LaVey loved music, playing in many venues of sorts.
My guess is sometime pre-1960, when he was playing the organ for a fee, he came accross a tune called Yankee Rose. After playing it for the first time in front of an audience, he decided to make the CoS. Thus, going about a new religion, and all it entails.
Having heard Dr. LaVey play the organ on many occasions, I can think of a hell of a lot worse sounds.
The organ is actually quite "satanic" as instruments go, because it is the only instrument that becomes what it needs to be to get its message across. It can sound like the oboe, wind whispering through the mellow tones, or carry undertones of trumpets, or drums far distant and coming to the fore... it can be sweet or it can rage. In the hands of a master, it can touch "the soul."
Bury your dead, pick up your weapon and soldier on.