The dead-eyed men are the priests of Kallum - the god worshiped by most on Ouloos as supreme ruler and creator of all things. Acting as messengers of his will, they appeared wherever he wished his word be spread or his law be enforced. Ymitoth cowered before them at Havenstahl while Maelich stood tall.
The lad of the Lake did not learn until far later in his journey that the dead-eyed men were soulless corpses animated by Kallum, the great Eagle and ruler of the sky. As such, they should have fallen lifeless when Maelich scattered the god. Without his will to sustain their dead flesh, they should have quickly begun to rot as any natural corpse would. But did they?
When Maelich returns to the Sobbing Forest at the beginning of Lake of Dragons: Kallum's Fury eighteen summers after his first visit, the triumphant return is interrupted by a frantic Cialia bearing horrific news. Ymitoth had returned to Havenstahl after a hunt, beaten and murmuring about dead-eyed men whose description bore an uncanny resemblance to Maelich's recollection of the three. How could that be?