Seisenki Elna Saga

The land in ELNA SAGA is called Gimrey, and supposedly in the far past, before magic became a part of every person, a great monster had swooped down from the north and ravaged the world. Fanning great gusts of destructive magical wind, it reduced nearly everything to empty wasteland before a knight appeared to challenge it.
Bearing a sacred sword and shield which repulsed magic, this knight finally struck the monster down after a tremendous battle. But this creature would not die, and as it lay immobile, the wind poured forth from its wounds unrelentingly. With the last of his strength, the knight planted his sword high atop the mountain where the battle had been fought, so that it would shield a part of the land from the wind. This was the beginning of Gimrey, and the reason why everyone is born with innate magic.
As time passed, people began to fight over fertile ground. ELNA SAGA begins right before the outbreak of yet another war, and tells of a princess named Elna. Born without any magic whatsoever and as such being the only person who can actually touch the sacred sword guarding Gimrey, she becomes a pawn used by her kingdom to threaten other countries with destruction. A rival kingdom's assassination attempt turns rescue, however, when the ones behind this plot reveal that they have no qualms about killing Elna as long as they can maintain a facade using a lookalike. With the help of her would-be assassin, who is drawn to her innocence and compassion, Elna journeys to define herself and stop a terrible war that her country has started.
The first thing one notices is the richness of the world in which this series has been set. The ideas behind ELNA SAGA are drawn loosely from Nordic culture and mythology and the story, people, and names all bear a medieval Northern European flavor. There are no gods or non-human races, but Valkyries, Berserks, and the world tree Yggdrasil make their appearance in one form or another, and the castles and towns evoke nostalgic memories of old storybooks.