international craziness started well before the all of the western roman empire (where as the eastern empire lasted a good bit longer).
the romans, in particular had intense political craziness with everyone with in arm reach of them since forever...
rome / egypt
rome / persia
if mid to northern europe and spain had been organized into proper countries prior to rome's visists, then they would have been nuts aslo. they mostly had the good sense to stay tribal for many decades past the introduction of countries to them.
even so,
we like to forget that most of western europe (not in the arctic circle) was one country until bickering among some idiot kids broke it up into the modern spain/france/germany. kids can break anything.
i will admit, i have not looked up when the various kingdoms in northern europe started, but they were very limited untill after the last period of enlightenments ended. a couple cities does not a country make.
it should also be mentioned that the 'stupid' polish invented pants. if it were not for them we would all be in robes and kilts.
it was also the 'stupid' polish that raided the snot out of western rome and subsequently contributed to its demise, with the help of the arctic circle gang of course...