Ethnicity, politics, religion have been a serious cause of division among the nations of Eastern Europe.
Eastern Europe is the eastern part of the European continent.
There exist important definitions of this region, one is the cultural dimension which indicates that the countries of Eastern Europe have some Greek, Russian, Byzantine, Eastern Orthodox, and traces of the Ottoman culture.
There is no agreement on the exact area it covers, partly because the term carries a wide range of geopolitical, geographical, cultural, and socioeconomic connotations.