Mercenaries in the third age(and middle earth more generally)

[Zigûr]

Originally Posted by Kuruharan

The only use of mercenaries in the classically understood sense by that name that I can recall is in The Nauglafring when the dwarves hire orcs to help them.

That is an early version of the chapter "Of the Ruin of Doriath" and the detail of the dwarves hiring orcs was not retained.

Letter 183 also offers this small morsel in relation to the moral position of the participants in the War of the Ring:

...even if in desperation 'the West' had bred or hired hordes of orcs and had cruelly ravaged the lands of other Men as allies of Sauron...

This seems to imply, however vaguely, that Professor Tolkien considered Orcs fighting for hire as at least a hypothetical possibility in 1956.