It Europe itself,the rise of national awareness at the end of eighteenth century Spread across Europe from west to east.
By the middle of the century , nationalist leaders and thinkers were already thinking in terms of an exclusivist doctrine calling for the "nation" to correspond with the "state,
That is, to make political borders correspond with ethnic or linguistic borders.
Carrying out such exclusivist ethnic nationalism was approached in a number of ways in various settings, and a number of small states moved toward policies of ethnic exclusion in the nineteenth century. It was on the peripheries of the great European empires ( including especially the Ottoman Empire) that a sharp-edged,ethnicity-oriented policy led to a variety of policies of forced assimilation, expropriation of property, violence, and in several cases, mass killing.