Nobunagun (2014)

Earth is under attack from otherworldly creatures known as Evolutionary Invasion Objects, and only the agents of DOGOO, a government organization, can keep the monsters at bay. Armed with special weapons infused with the souls of distinguished historical figures, these fighters, recruited by an alien who watched its planet be destroyed by the Objects, are humanity’s best chance against the invaders. Teenager Shio Ogura used to be nothing but a loner and a military otaku, until one day she and her class went on a field trip to Taiwan and found themselves smack dab in the middle of an Object attack. To help save a new friend, the girl picks up a gun infused with the famed samurai Nobunaga Oda, thus securing her fate as the newest member of DOGOO, and protector of humanity!