Little Richard is the “Architect of Rock and Roll” (he’s also the “King of Rock and Roll,” along with several others—neither Run nor D.M.C. among them).
Lady Gaga is the “Princess of Electropop.”
There are three “queens of Tejano” and six “queens of Rock and Roll,” Gwen Stefani inexplicably one of them.
Jully Black is the “Queen of Canadian R&B.” (I don’t think I’ve ever heard of her before.)
“His Purple Majesty”: Prince, duh.
There are two “princesses of Wails”—Charlotte Church and Cerys Matthews—both from Wales, interestingly enough.
Pavarotti is the “King of the High Cs.”
In the East, there are the “Four Heavenly Kings of Chinese Pop”: Jacky Cheung, Leon Lai, Andy Lau, and Aaron Kwok.
Back in the West, there’s the “Big Four of Thrash”: Anthrax, Metallica, Megadeth, Slayer.
Clapton is, of course, “God.”
I really love this list of honorific titles in popular music on Wikipedia.