Izetta: The Last Witch

The time is pre-World War II and the setting is a European-like imaginary world. A large-scale war erupts and bloody battles are taking place throughout the world. Eylstadt is a small country that lacks a strong military force and natural resources. Finé, who is the crown queen of Eylstadt, decides to use a secret weapon against larger countries, in a time where battling against larger countries was unthinkable. The secret weapon is a witch named Izetta, who uses her magical force to fight. The young witch Izetta is the last survivor of her kind, and is notable for her burning red hair.

(Source: Crunchyroll)