Eastern europe is full of grunges that have been mostly unresolved, full of lively ideologies and nationalism is not a dirty concept there. If you listen, they each will list at least all the major reasons they hate each other from the past century and a half, bound to mention at least one reason why those sons of bitches from Ruritania are a bunch of turks/mongols/nazis/commies. They also have been most active conscriptors and thus, military service isn't that big of a choice for them compared to countries that have relied purely on professional militaries. Also, consult the following chart from 2015 and you'll see where nationalism is at it's strongest. The numbers only have grown from this.
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