I agree with the Nordic idea; most of the evidence of the song seems to fit. However, I think Zep were also having a bit of fun with their new American audience; they started, as we all know, in Britain, and the wave of post-Beatles bands in America may here be termed 'an invasion'.
In effect, I think it's comparing a historical event to what was transpiring at the time of the song's writing.
I agree with the Nordic idea; most of the evidence of the song seems to fit. However, I think Zep were also having a bit of fun with their new American audience; they started, as we all know, in Britain, and the wave of post-Beatles bands in America may here be termed 'an invasion'.
In effect, I think it's comparing a historical event to what was transpiring at the time of the song's writing.