by Nadia F., a Russian woman living in St Petersburg, Russia
The Baltic Sea is located in Northern Europe, bounded by the Scandinavian Peninsula, the mainlands of Northern Europe, Eastern Europe, Central Europe, and the Danish islands. It drains into the Kattegat by way of the Öresund, the Great Belt and the Little Belt. Kattegat then continues in the Skagerrak into the North Sea and the Atlantic Ocean.
The Baltic Sea is linked to the White Sea by the White Sea Canal and directly to the North Sea by the Kiel Canal.
The first one to name it the Baltic Sea was Adam of Bremen and he seems to have based it on a large island, Baltia, mentioned by Xenophon and located in northern Europe. It is possibly connected to the Germanic belt, a name used for some of the Danish straits, while others claim it to be derived from Latin balteus (belt). From this use, Baltic has been applied to the Baltic countries. Another proposed derivation from the Indo-European root *bhel meaning white, shining seems speculative.
As the ground rose after being pressed down by the ice, the Baltic Sea switched between being a sea and a lake, or something in between, and it was variously connected to the North Sea-Atlantic either through the straits of Denmark or at what are now the large lakes of Sweden, and the White Sea-Arctic Sea. Many of the stages are named after certain marine animals (like the Littorina mollusc) that are clear markers of changing water temperatures and salinity.
The Baltic Sea somewhat resembles a riverbed, with two tributaries (the Gulf of Finland and Gulf of Bothnia). From geological surveys it has become apparent that there indeed was a river in the area in the Pleistocene: the Eridanos.
Due to the Post-glacial rebound, the ground is still rising after having been released from the weight of the Weichsel glaciation, especially around the Gulf of Bothnia: at places the ground is rising by almost one metre per century, which means that the shore can gain dozens and in some shallow places hundreds of meters in a human lifetime.
At the time of the Roman Empire, the Baltic Sea was known as the Mare Suebicum or Mare Sarmaticum. Tacitus in his AD 98 Agricola and Germania described the Mare Suebicum, named for the Suebi tribe, during the spring months, as a brackish sea when the ice on the Baltic Sea broke apart and chunks floated about. The Sarmatian tribes inhabited Eastern Europe and southern Russia. Jordanes called it the Germanic Sea in his work the Getica.Since the Viking age, the Scandinavians have called it "the Eastern Lake" (Austmarr, "Eastern Sea", appears in the Heimskringla), but Saxo Grammaticus recorded in Gesta Danorum an older name Gandvik, "-vik" being Old Norse for "bay", which implies that the Vikings correctly regarded it as an inlet of the sea. (Another form of the name, "Grandvik", attested in at least one English translation of Gesta Danorum, is likely to be a misspelling.)
In addition to fish the sea also provides amber, especially from its southern shores. The bordering countries have traditionally provided lumber, wood tar, flax, hemp, and furs. Sweden had from early medieval times also a flourishing mining industry, especially on iron ore and silver. Poland had and still has extensive salt mines. All this has provided for rich trading since the Roman times.
In the early Middle Ages, Vikings of Scandinavia fought for power over the sea with Slavic Pomeranians. The Vikings used the rivers of Russia for trade routes, finding their way eventually all the way to Black Sea and southern Russia.
Finland and the Baltic states were the last in Europe to be converted into Christianity in the Northern Crusades: the former in the 12th century by the Swedes and the latter in the 13th century by the Germans. First the Livonian Brothers of the Sword and then the powerful German Teutonic Knights held the Baltic countries and fought with Danes and the Swedes, while the foundations of Russia were being laid in Novgorod.
Later on, the strongest economic force in Northern Europe became the Hanseatic league, which used the Baltic Sea to establish trade routes between its member cities. In the 16th and early 17th centuries, Poland, Denmark and Sweden fought wars for Dominium Maris Baltici (Ruling over the Baltic Sea). Eventually, it was the Swedish empire that virtually encompassed the Baltic Sea. In Sweden the sea was then referred to as Mare Nostrum Balticum (Our Baltic Sea).
In the 18th century Russia and Prussia became the leading powers over the sea. Russia's Peter the Great saw the strategic importance of the Baltic and decided to found his new capital, Saint Petersburg at the mouth of the Neva river at the east end of the Gulf of Finland. There was much trading not just within the Baltic region but also with the North Sea region, especially the eastern England and the Netherlands: their fleets needed the Baltic timber, tar, flax and hemp.
During the Crimean War a joint fleet of Britain and France attacked Russian fortresses by bombarding Sveaborg that guards Helsinki and Kronstadt that guards Saint Petersburg and destroying Bomarsund in the Åland Islands. After the unification of Germany in 1871, the whole southern coast became German. The First World War was fought also on the Baltic Sea. After 1920 Poland returned to the Baltic Sea, and Polish ports of Gdynia and Gdan'sk became leading ports of the Baltic.
During the Second World War Germany reclaimed all of the southern shore and much of the eastern by occupying Poland and the Baltic states. In 1945 the Baltic Sea became a mass grave for drowned people on torpedoed refugee ships. As of 2004, the sinking of the troopship Wilhelm Gustloff remains the worst maritime disaster of all time, killing (very roughly) 9,000 people.
After 1945 the sea was a border between conflicted military blocks: in case of military conflict in Germany, in parallel with a Soviet offensive towards the Atlantic Ocean, communist Poland's fleet was prepared to invade Danish isles.
In May 2004, the Baltic Sea became almost completely a European Union internal sea when the Baltic states and Poland became parts of the European Union, leaving only the Russian metropolis of Saint Petersburg and the enclave of Kaliningrad as non-EU areas.
The Baltic Sea starts to get very rough with the October storms. These winter storms have been the cause of many shipwrecks, like for example the Estonia in 1994. But thanks to the cold brackish water where the shipworm cannot survive, the sea is a time capsule for centuries-old shipwrecks. Perhaps the most famous one is the Vasa.