Then there's Dwarves versus Foul Folk (a war started when Grg hurled Durek into the Vorvor); Elves versus Foul Folk; in fact, lots of people versus Foul Folk.
There's Mage against Black Mage (they're Mages all).
But Elves no longer fight Elves (the philosophy of "Let it begin with me" stopped that).
Dwarves have some conflict among themselves, but only on a personal basis, for they revere "honor" above all.
Warrows only have small tiffs among themselves. They are simply too pastoral and too optimistic to fall into great struggles among themselves.
When you think of it, most big fights start over: water; religion; resources; land. In Mithgar, there's lots of unoccupied land, lots of water, resources (such as iron, gold, other minerals, oil, etc.) only become real important when the technology reaches a certain point.
Also, Dwarves occupy a certain niche that others do not want for themselves. Elves occupy a different niche. Warrows, even a different niche. Hidden Ones are quite lethal, and so no one messes with them.
Hence, it's humans who struggle against humans (for various causes, some of which are listed above).
Finally, beyond the strictly human conflicts, religion is the main source of war on Mithgar which sweeps nearly everyone up on it's cruel embrace, and then it's primarily the forces of Gyphon versus those of Adon.
Let me add a post script: The stories in the Mithgarian Mythos are all connected by an overall theme. The conflicts among humans simply don't fall into the overall theme I was writing about.
Someone asked me awhile back, why didn't I write about the War of the Usurper. My reply is that that war was about who should be the rightful High King, and it didn't fit into the overall story arc. That tale, by the way, has plenty of treachery and treason involved, but it wasn't one I wanted to tell.
As far as everyone getting along in my stories (that is, the "good guys" getting along with one another), generally speaking, when faced with a common threat (a really big common threat), folks do indeed "get along" until that threat is dealt with.
That, plus the fact that the niches the various races fit into are sufficiently different that one race doesn't envy another, nor lust after the other's possessions, etc. Besides, they know that going after something of the other's goods, well, they'd be at a helluva disadvantage. For example, if Elves invaded a Dwarvenholt, the Elves'd be toast. Same with the Dwarves invading an Elven realm: Dwarf toast, anyone? Likewise, the same holds with Hidden Ones and other such. And Warrows when riled are quite devastating. As for Magekind, what would they want from others that they can't have on their own; for Black mages, it's "fire." I believe that only Dragons and Utruni have the power to take down almost anyone they would go up against, but again I ask, what would they like to gain? Treasure for the Dragons, perhaps. For the Utruni ... who can say?
That's enough for now.
-Dennis