Incantations... ?

[HerenIstarion]

All right, than here it comes:

Under the Mountain dark and tall
The King has come unto his hall!
His foe is dead, the Worm of Dread,
And ever so his foes shall fall.

The sword is sharp, the spear is long,
The arrow swift, the Gate is strong;
The heart is bold that looks on gold;
The dwarves no more shall suffer wrong.

The dwarves of yore made mighty spells,
While hammers fell like ringing bells
In places deep, where dark things sleep,
In hollow halls beneath the fells.

On silver necklaces they strung
The light of stars, on crowns they hung
The dragon-fire, from twisted wire
The melody of harps they wrung.

The mountain throne once more is freed!
O! wandering folk, the summons heed!
Come haste! Come haste! across the waste!
The king of friend and kin has need.

Now call we over mountains cold,
'Come hack unto the caverns old'!
Here at the Gates the king awaits,
His hands are rich with gems and gold.

The king is come unto his hall
Under the Mountain dark and tall.
The Worm of Dread is slain and dead,
And ever so our foes shall fall!

whom and where