The series is set in an alternate history Earth in which the United States of America is actually the United States of Columbia, magic is real, and the First World War is fought with and by dragons, spells, vampires and all other kinds of magical weapons and beings.
The story follows the protagonist, Fletcher Arrowsmith, as he joins the war effort on the side of the Allies, gets taught the rudiments of sorcery and engages in some brutal battles with the enemy Prussians.