Tenabran Trilogy

The Tenabran trilogy is a fantasy trilogy by Dave Luckett, consisting of A Dark Winter, A Dark Journey, and A Dark Victory.

In the first book, rumours arise that the Evil Overlord, defeated long ago, is returning. Things get worse from there.

This series provides examples of:

 * Exclusively Evil: Subverted. Goblins are thought to be, because they only time they've interacted significantly with humans was as the Evil Overlord's mooks; it turns out that they're actually a peaceful and artistic people when left to themselves, but as a species they have a low resistance against telepathic domination that makes them really handy to anyone with mind-control powers and a sudden desire to field an army.
 * The Empire: The Big Bad is the Emperor. He isn't an Evil Overlord, just a regular historically-plausible dictator; in the long run, much more dangerous.
 * Evil Overlord: Deconstructed. The author started writing it to explore questions like "Just what does the Evil Overlord get out of lurking in Mordor and trying to take of the world?" and "Where does he get the Exclusively Evil cannon fodder from?"
 * Left Justified Fantasy Map: There's a map, bordered with an ocean on the west, but the usual associations are inverted -- instead of having the Evil Overlord in the east, the heroes living in the west, and an Avalon-equivalent over the ocean, the heroes live in the east and the Evil Overlord's heartland is over the ocean to the west. There are watchtowers all along the coast.
 * Magic Is Evil: A lot of people believe this. The Sorcerous Overlord probably had something to do with it, but it's also pointed out in A Dark Journey that magic is by definition unnatural: magic causes things to happen that go against the laws of nature, that's how you know it's magic.
 * Medieval European Fantasy: Written by somebody who's studied actual medieval history, not just read a lot of earlier Medieval European Fantasy.
 * Our Goblins Are Wickeder: See above under Exclusively Evil. When they're not being enslaved by the Sorcerous Overlord, they're the closest thing this setting has to Our Elves.
 * Puppet State: In A Dark Winter, the protagonist's homeland has become a puppet state of The Empire. A significant plot point concerns the revelation of how far another character is prepared to go secure its independence.
 * Sorcerous Overlord: The Evil Overlord is of this type.
 * Two-Part Trilogy: Winter was originally written as a standalone novel. Journey and Victory were plotted together after the publisher started thinking in trilogies, and form two parts of a single story.