>>717819548
>have the same culture
Not exactly.
>have the same religion
Half are Catholic and the other half is Orthodox, not exactly homogenous.
>why dont they form a big country, like a slavic empire like the Germans, indians or chinese do
Only Russia succeeded in that, other attempts at some form of a big country failed miserably like Poland-Lithuania due to religious division and dogshit political system, or Yugoslavia which came a century or two to late to form a united national identity.