The Northern Future Forum, the Nordic Investment Bank and Nordic Battlegroup are other examples of Northern European cooperation that includes the three Baltic states that make up the Baltic Assembly.
The Caucasus nations of Armenia, Azerbaijan, and Georgia are included in definitions or histories of Eastern Europe.
The Baltic states have seats in the Nordic Council as observer states.
They also are members of the Nordic-Baltic Eight whereas Eastern European countries formed their own alliance called the Visegrád Group.
Another definition was used during the 40 years of Cold War between 19, and was more or less synonymous with the terms Eastern Bloc and Warsaw Pact.
Euro Voc, National Geographic Society, Committee for International Cooperation in National Research in Demography, STW Thesaurus for Economics place the Baltic states in Northern Europe whereas the CIA World Factbook and UNESCO place the region in Eastern Europe with a strong assimilation to Northern Europe.
The East–West Schism which began in the 11th century and lasts until the present, divided Christianity in Europe, and consequently the world, into Western Christianity and Eastern Christianity.
There is no consensus on the precise area it covers, partly because the term has a wide range of geopolitical, geographical, cultural, and socioeconomic connotations.Owing to the rivalry between Parthian Iran and Rome, and later Byzantium and the Sassanid Persians, the former would invade the region several times, although it was never able to hold the region, unlike the Sassanids who ruled over most of the Caucasus during their entire rule.The earliest known distinctions between east and west in Europe originate in the history of the Roman Republic.There are "almost as many definitions of Eastern Europe as there are scholars of the region".
One definition describes Eastern Europe as a cultural entity: the region lying in Europe with the main characteristics consisting of Greek, Byzantine, Eastern Orthodox, Russian , and some Ottoman culture influences.In some media, "Central Europe" can thus partially overlap with "Eastern Europe" of the Cold War Era.