Tales of Luminaria the Fateful Crossroad

Long ago, this land was home to beasts the size of mountains.Mana overflowed from their remains, drawing people who sought that power, and civilizations sprang up. People came to revere these mana-producing creatures, which they named "Primordial Beasts." They built their lives around them. Thus began the worship of the Primordial Beasts. Time flowed ever onward, to the present day. War erupts between the Jerle Federation, an alliance of countries who worship the Primordial Beasts, and the Gildllan Empire, which has enjoyed explosive development thanks to advanced technology. The fires of war are stoked with each passing day. Leo, a young federation knight-in-training, heads out to complete a mission in Lunne, a town formerly under imperial control, now located near the border. With him are his childhood friend and fellow trainee, Celia, and their instructor, Lisette. Who should be waiting for them but Hugo, a former friend turned traitor to the federation, now a soldier of the empire.

Synopsis from Anime News Network