Can anyone be said to have done so? Or was it just a movement that emerged from the various people playing at the time? I believe that Kind of Blue was the first album to popularize it but can Miles actually be said to have invented modal Jazz? Surely other contemporary musicians were doing similar things.
Wikipedia is not very clear on this. It states
Originating in the late 1950s and 1960s, modal jazz is epitomized by Miles Davis's "Milestones" (1958), Kind of Blue (1959), and John Coltrane's classic quartet from 1960–64.
And then goes on to say
Mercer Ellington has stated that Juan Tizol invented the melody to "Caravan" in 1936 as a result of his days studying music in Puerto Rico, where they couldn't afford much sheet music so the teacher would turn the music upside down after they had learned to play it right-side up.
So, if Caravan is indeed the first modal jazz piece, should Juan Tizol be credited with inventing it? Or should it be Russel? Or everyone who was playing at the time or what?