Who am I thanking?

Thank you for the music ... cue for a song. But I've been pondering. Who am I thanking?

Ancient peoples making random harmonious sounds, that's music. But for me to pick up a piece of sheet music and be learning to sing it (I've joined a choir), or play on the new digital piano that Santa brought, there has to be musical written language - notation.
Who thought originally of doing this?
(I'm reminded of the joke about milking a cow - who was the person to think 'what a good idea, we'll pull at that critter's udders').
And visually and structurally, with staves and bar lines and dotty notes, written music follows the same rules whether I'm reading the music for 'when the saints go marching in' or a piece of Mozart. So do all nationalities, with all their different languages (Greek, Japanese, Swahili?) all start learning notation with the 'Every Good Boy Deserves Favour' mnemonic?
Hmmmm ...
Any answers or insights anybody?