The Dawn Men were the race of creatures from which the Elenes, Styrics, and presumably the other human races of Daresia and Eosia, as well as the Trolls, were descended. By the time of The Elenium and The Tamuli, these creatures were long extinct; due to a ressurection spell worked by Zalasta, however, Sparhawk and his allies encountered them in The Sapphire Rose, and are intimated to be seen during the events in The Tamuli (though aside from a few brief references, they are completely unseen in the latter case).
The Dawn Men are described as looking vaguely like much larger, more humanoid Trolls, but wearing primitive jewelery and makeup. They are extremely brutish and agressive, and have a thick hide that can withstand normally debilitating injuries. According to Stragen, their hearts are also lower on their bodies, closer to the belly. They appear to communicate via grunts and shrieks.
Despite their primitive nature, they do show some glimmers of higher intelligence, such as their making of primitive clothing, jewelery, and weapondry. They also fight battles in formations, a trait they share with their distant Elene kindred. (Interestingly enough, the Elenes and Cyrgai seem to be the only ones who utilize these tactics, which shows their comparatively uncivilized status.) They are, as Ulath puts it, "herd animals", and so will accept nearly any member of their species. It is implied that each herd is led by a dominant member, and their primitive behavior likewise suggests a patriarchal society; it is possible, however, that they may follow a matriarchal structure, or an otherwise gender-neutral structure that distributes authority via another method.