If I am promised to the princess, then I will fight for her sake. 

In 1939 C.E., the imperialist nation of Germania invaded a neighboring country. All at once, that war spread throughout Europe, and the era was dragged into a spiral of a great war. 

Then, in 1940, Germania's attack turned towards the Principality of Eylstadt, a small Alps country abundant with beautiful water and greenery. 

(Source: Official Website)

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