Sorry for not responding earlier, I was a little confused by the title "King of the Fairies." As far as I know the "King of the Fairies" is an instrumental for a set dance.

By chance I happen to know a little poem from my schooldays, and I think it may be the one you want. When we learned it the title was "Up the Airy Mountain."

It's the same as "Big Daddy's" submission with the first verse repeated. The third verse I got from an earlier thread.

Up the airy mountain, down the rushy glen,
We dare not go a-hunting for fear of little men.
Wee folk, good folk, trooping all together,
Green jacket, red cap and white owl's feather.

Up the craggy hillside, through the mosses bare,
They have planted thorn trees for pleasure here and there.
Is any man so daring as to dig them up for spite?
He'll find their sharpest thorns in his bed that night.

High up on the hilltop the old king sits.
He's now so old and grey, he's nearly lost his wits.
He's rising with the music on the cold starry night,
To sup with the queen of the gay north light.

Up the airy mountain, down the rushy glen,
We dare not go a-hunting for fear of little men.
Wee folk, good folk, trooping all together,
Green jacket, red cap and white owl's feather.