Roger Waters for the most exceptional philosophical lyrics in the history of music.

Probably like...... I dunno let me think about it.

Why 20th century and not all time? I think Leonin is probably the biggest - he kind if pioneered polyphony?

If we are talking lyrics then Bob Dylan. Hendrix is a good call.

I would say Mick Jagger....because he will likely be only rocker who would outlive English queen. Other than that I value Jim Morrison highly.

Uh oh, we're already at Syd Barrett vs. Roger Waters.

I'm going to go with Elvis. Granted, he basically just put a white face on existing black music, but he created the idea of the "rock star."

Since we talk the most revolutionary, I go with Arnold Schoenberg.

Elvis was an exceptional but wasted talent alas. Love his early work. The 68 special was great tool

This debate depend on the type of music... Popular, Jazz, Classical .... Very different realms.

... great *too

well, if we're talking about pioneering surely chuck berry shouldn't be left behind

maybe not as influential as many of the aforementioned but for sure revolutionary

I wonder if we'd be talking about Elvis like that had not a small plane fall down on Feb 3rd 1959...

hey....how about guido d'arezzo? He thought up modern notation, solfège and virtually made possible to everyone (interested) learn, compose and communicate his/her musical ideas easily.

I think the most revolutionary lyricists were Lennon/McCartney, just the freshest and best songwriting duo of that time...

As for most revolutionary overall...it'd have to be someone who transitioned between jazz and rock...

Lin, we're talking 20th century.

Well, Cachimbo, there's no doubt Buddy Holly belongs in the conversation as well, and I'd say Little Richard too.

Buddy Holly.. :( Listen to a lot of his songs on my ipod...he was such a talent...could of made so many more songs.. Wish I could of been born back then.

Oh not saying I think he was most Revolutionary Person in Music(20th Century)..but he is up there.

If anything I would have to go with Freddie Mercury. But that is me..and I am young..maybe Im blind haha

hmmm, no jazz lovers? Charlie Parker? Louis Armstrong?

@Riphen: Hahaha!

It's not just that Buddy Holly was a great talent, it's also that 2 other big names disappeared from the map, leaving it quite open for the guy who was playing similar music to walk in and take the space.
Don't take me to be saying Elvis didn't belong there, though. But if someone puts Elvis in this list of revolutionaries, I think it would be more appropriate to name the whole band that was travelling with him in the late 50s: Cash, Holly, Valens, Jerry Lee, etc.

@Goldy:

Miles?

Coltrane?

Yeah, Miles was a game-changer too. I'm more of a Louis Armstrong fan though.

Blind Lemon Jefferson.

i second mapleleaf actually. popular american music was the music of the 20th century, and blues spawaned all forms of popular music. Blind Lemon Jefferson was one of the first in blues; this makes him the most revolutionary.

maybe dj kool herc takes number two, and im sure louis armstrong and chuck berry deserve mentions

Gershwin comes to mind as well...

and Kurt Weil

If we're talking about music as a whole I feel like Les Paul has to be on the list and high on it

I'm not well versed in music enough to confidently declare a #1 most revolutionary musician, but Kurt Cobain was also definitely a game changer.