Which forces would make thematic allies for a Dwarven army??

Arnor warriors and rangers used as men of dale, elves depending on the time your army is based on, and maybe arnor units used as arnor. That's pretty much it.

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Ours is the fury!

Some say Dwarves took part in the Last Allliance.

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"I am the Flying Spagetti Monster. Thou shall have no other monsters before me"
-FSM.

I'd say they could allie with the forces of the Blue Wizards!!!!

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Free speech carries with it some freedom to listen. -B.M.

You could go with men of dale as others have suggested, but I would use Warriors of Rohan in stead of Warriors of arnor. That takes away your spears though. Mirkwood could always work, even though they only fought togheter once. Eregion + Khazad Dum is not a bad theme either.

Elves of mirkwood, theme:they fought together once or twice,game:they give you a shooting advantage by a lot.

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If you don't let me in, Frodo, I shall blow your door right down your hole and out through the hill-Gandalf

Men of Arnor (blue mountains dwarves), Rohan (4th age, from the Glittering Caves of Helm's Deep, or proxy as Men of Dale) or Gondor (Last Alliance).

But largely Dwarves are a very secretive, ally-less people.

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"... Telchar wrought it in the deeps of time."
-On Andùril, The Lord of the Rings

not really. it says dain was a great freind of dale.

I'd go for dale if i were you.

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'Though my memory's fading, I remember two things very clearly: I am a great sinner and Christ is a great Savior'
-John Newton

Dale doesn't really count because it sits at the base of Erebor. Dain was also one of the first dwarf leaders in several generations to willing ally himself with other kingdoms, one of which was an elf one.

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"Leave Sauron to me."
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