The Baltic states or the Baltic countries is a geopolitical term encompassing Estonia, Latvia, and Lithuania. All three countries are members of NATO, the European Union, the Eurozone, the Baltic Assembly, and the OECD. The three sovereign states on the eastern coast of the Baltic Sea are sometimes referred to as the "Baltic nations", less often and in historical circumstances also as the "Baltic republics", the "Baltic lands", or simply the Baltics.
The region was inhabited by various peoples including the Baltic tribes between antiquity, Christianization, and Middle Ages but they have been subjugated by various foreign rules before their colonizations by the Russian and German Empires respectively. Near the end of World War I in 1918, all three Baltic states became independent countries but their sovereignty was interrupted by the start of World War II when the Soviet Union at first, began to occupy and annex all three Baltic states in 1940, followed by Nazi Germany in 1941, then re-occupation by the Soviets in 1944 where they then faced isolation from the outside world. In 1989, during the anti-communist upheavals in Eastern Europe, the Baltic states struggled to regain their independence from Soviet domination, which culminated in their restorations of independence in 1991 when the Soviet Union disintegrated.
Since their restorations of independence, all three Baltic countries are classified as high-income economies by the World Bank and maintain a very high Human Development Index. The three governments engage in intergovernmental and parliamentary cooperation. There is also frequent cooperation in foreign and security policy, defence, energy, and transportation.
The term Baltic stems from the name of the Baltic Sea – a hydronym dating back to at least 3rd century B.C. (when Eratosthenes mentioned Baltia in an Ancient Greek text) and possibly earlier. There are several theories about its origin, most of which trace it to the reconstructed Proto-Indo-European root *bhel meaning 'white, fair'. This meaning is retained in the two modern Baltic languages, where baltas in Lithuanian and balts in Latvian mean "white". However, the modern names of the region and the sea that originate from this root, were not used in either of the two languages prior to the 19th century.
Since the Middle Ages, the Baltic Sea has appeared on maps in Germanic languages as the equivalent of 'East Sea': German: Ostsee, Danish: Østersøen, Dutch: Oostzee, Swedish: Östersjön, etc. Indeed, the sea lies mostly to the east of Germany, Denmark, Norway, and Sweden. The term was also used historically to refer to the overseas provinces of Sweden (Swedish: Östersjöprovinserna) and, subsequently, the Baltic governorates of the Russian Empire (Russian: Остзейские губернии, romanized: Ostzejskie gubernii). Terms related to modern name Baltic appear in ancient texts, but had fallen into disuse until reappearing as the adjective Baltisch in German, from which it was adopted in other languages. During the 19th century, Baltic started to supersede Ostsee as the name for the region. This change was a result of the Baltic German elite adopting terms derived from Baltisch to refer to themselves. Its Russian derivative Pribaltiyskiy (Прибалтийский) was first used in 1859.
The term Baltic countries or Baltic Sea countries has also sometimes been used in the context of countries neighbouring the Baltic Sea, the Baltic Region, including prior to 20th century. After World War I, the new sovereign states that emerged on the east coast of the Baltic Sea – Estonia, Latvia, Lithuania, and Finland – became known as the Baltic states. Since World War II, the term has been used to group the three countries Estonia, Latvia, and Lithuania.
History before the 20th century
Although the modern Baltic states – Estonia, Latvia, and Lithuania – share a geographical region and certain historical experiences, their pre-modern paths diverged sharply. Geography, ethnic composition, and the sequence of foreign conquests all shaped distinct political and cultural developments.
From the early Middle Ages, the territories of present-day Estonia and Latvia were inhabited by a mosaic of Finnic and Baltic tribal societies, including the Estonians, Livs, Curonians, Semigallians, Latgalians, and Selonians. Farther south, in the lands that would later form Lithuania, related Baltic tribes such as the Lithuanians, Samogitians, Yotvingians, and Skalvians inhabited the region's forests and river valleys. These groups shared linguistic and cultural ties with their northern neighbours but developed distinct local identities and systems of governance. Their settlements, typically fortified hillforts surrounded by agricultural lands, served as both defensive centers and hubs of trade connecting the Baltic coast to inland routes leading toward Rus' and central Europe.
In the 12th and 13th centuries, the northern and western parts of the region – modern Estonia and Latvia – became targets of Christianization and conquest. German crusaders, supported by papal sanction and local bishoprics, launched the Livonian Crusade to subdue the pagan populations. The Livonian Brothers of the Sword, later absorbed into the Teutonic Order, established a series of strongholds and ecclesiastical territories that brought Estonia and much of Latvia under foreign domination. These crusading states introduced Western feudal structures, imposed Christianity, and subordinated native peoples within a hierarchy led by German military and clerical elites. Urban centers such as Riga, Tallinn (Reval), and Cēsis (Wenden) grew under German law and became prosperous members of the Hanseatic League, facilitating trade in grain, furs, timber, and wax between the Baltic and western Europe. However, political power remained concentrated in the hands of German-speaking landowners and clergy. The indigenous Estonian and Latvian populations were largely reduced to serfdom, forming a rural majority excluded from civic governance.
Lithuania followed a markedly different course. The Lithuanian tribes, situated further inland and less accessible to seaborne crusaders, remained outside the control of the Livonian and Teutonic Orders. Their inland position, fragmented political structure, and ability to mount coordinated resistance allowed them to avoid subjugation and later unite under native leadership. In the 13th century, these tribes coalesced under native rulers, most notably Mindaugas, who was crowned king in 1253 and established the Grand Duchy of Lithuania. Unlike its northern neighbours, which were absorbed into foreign feudal systems, Lithuania retained its indigenous leadership and gradually consolidated a centralized authority. Through a combination of military campaigns, strategic marriages, and pragmatic alliances, the Grand Duchy expanded rapidly during the 14th and 15th centuries, extending over much of present-day Belarus, Ukraine, and parts of western Russia. This expansion brought together diverse peoples and faiths under Lithuanian rule, creating one of the largest and most multi-ethnic states in medieval Europe. The ruling elite adopted aspects of Western and Eastern political traditions, maintaining their native faith longer than most of Europe before the official Christianization of Lithuania in 1387 under Grand Duke Jogaila.
As Lithuania grew, it entered into a close dynastic relationship with Poland through Jogaila’s marriage to Queen Jadwiga, leading to the Polish–Lithuanian union. While this partnership increased Lithuania's influence in central and eastern Europe, it also gradually integrated it into the political orbit of Poland. Nevertheless, Lithuania preserved its own institutions – its code of laws, administrative structures, and language of governance – long after the formal establishment of the Polish–Lithuanian Commonwealth in 1569. During the 16th and 17th centuries, the Commonwealth became a major power in central and eastern Europe, repelling Muscovite advances and influencing affairs across the region. However, the political liberties of the nobility and the growing power of magnate families gradually weakened central authority, leaving the state vulnerable to internal factionalism and external pressure.