There are thirteen episodes, and though it takes a long time to get into, because at there is a good deal of back tracking in the first three episodes, the action gets pretty good after word.
The story line basically goes, during the very last war of the Gods of Light, and the Gods of mayhem, the last Goddess of Light, and Goddess of Destruction met in a giagantic clash, which devestated the land,. and cut a piece of it off, creating the cursed island of Lodoss.
Thousands of years later, two kings, who at one time were best friends, became engulfed in warfare between their two nations, not realizing that there's a darker power trying to reawaken the Goddess of Destruction. Typical of this genre, a group of heroes, including a boy with a misterious path, an Elf, a swarf, a thief, a priest of the Sun God, and a mage go out to help the good king, discovering that a cursed mask, has taken over a certain young woman, in an attempt to claim power for the dark witch.
http://en.wikipedia.org/wiki/Record_of_the_Lodoss_War, Eh this link will tell you a lot more, because after the defeat of the dark witch, there's a new enemy, and then the mask possess the thief, while the evil king's high priest kinda stabs everyone in the back in his quest to reqawaken the goddess of destruction.
There are at least two other series based on this name, but the one I'm talking about is Record of the Lodos War the Black Witch.