They were, at first, a political jam band, a black MC5, if you will. America Eats Its Young, and all that. But black rockbands got as much attention in the 60s as 3-D smell-o-vision. Remember that the Jimi Hendrix Experience was a British (== "cool") band, and they had God playing guitar - Funkadelic weren't so advantaged, though you might describe them as the permanent Band of Gypsys that Hendrix was never able to muster together. And Sly came in through the soul door, belying, in part, his previous work.

Later on, the party became less explicitly political and more of a spectacle - the Mothership, the extensive mythology and plotline, etc. But there was a message in there somewhere, though only George could explain it. Maybe.

See also: Parliament, P-Funk, and Parliafunkadelicment Thang.