Marc Bolan emerged as the High Priest of Glamrock with T. Rex, he was part of a duo (first with Steve Peregrine Took and later Mickey Finn) known as Tyrannosaurus Rex. Formed in 1967 - Bolan, formerly with John's Children, got together with Took and formed an acoustic duo where Bolan played acoustic guitar (at first) and Took played bongos and they epitomized the breezy, stoned-out, somewhat incoherent aspect of 60's psychedelia. When Unicorn, their third album, came out in 1969 Bolan was already experimenting with a sound he would later morph into T. Rex. And since Unicorn would become Took's swan song (he would be fired shortly after), a new direction was in the cards.

This track, King Of The Rumbling Spires is actually the last collaboration with Steve Took from May 1969 and probably the first of what the eventual T. Rex would sound like.

After this, the rest was history.