<P> While Tacitus called it Mare Suebicum after the Germanic people called the Suebi, Ptolemy - Sarmatian Ocean, the first to name it the Baltic Sea (Mare Balticum) was the eleventh - century German chronicler Adam of Bremen . The origin of the latter name is speculative and it was adopted into Slavic and Finnic languages spoken around the sea very likely due to the role of Medieval Latin in cartography . It might be connected to the Germanic word belt, a name used for two of the Danish straits, the Belts, while others claim it to be directly derived from the source of the Germanic word, Latin balteus (belt). Adam of Bremen himself compared the sea with a belt, stating that it is so named because it stretches through the land as a belt (Balticus, eo quod in modum baltei longo tractu per Scithicas regiones tendatur usque in Greciam). He might also have been influenced by the name of a legendary island mentioned in the Natural History of Pliny the Elder . Pliny mentions an island named Baltia (or Balcia) with reference to accounts of Pytheas and Xenophon . It is possible that Pliny refers to an island named Basilia ("kingdom" or "royal") in On the Ocean by Pytheas . Baltia also might be derived from "belt" and mean "near belt of sea (strait)." Meanwhile, others have suggested that the name of the island originates from the Proto - Indo - European root * bhel meaning white, fair . This root and its basic meaning were retained in both Lithuanian (as baltas) and Latvian (as balts). On this basis, a related hypothesis holds that the name originated from this Indo - European root via a Baltic language such as Lithuanian . Another explanation is that, while derived from the aforementioned root, the name of the sea is related to names for various forms of water and related substances in several European languages, that might have been originally associated with colors found in swamps (compare Proto - Slavic * bolto "swamp"). Yet another explanation is that the name originally meant "enclosed sea, bay" as opposed to open sea . Some Swedish historians believe the name derives from the god Balder of Nordic mythology . </P> <P> In the Middle Ages the sea was known by variety of names . The name Baltic Sea became dominant only after 1600 . Usage of Baltic and similar terms to denote the region east of the sea started only in 19th century . </P> <P> The Baltic Sea was known in ancient Latin language sources as Mare Suebicum or Mare Germanicum . Older native names in languages that used to be spoken on the shores of the sea or near it usually indicate the geographical location of the sea (in Germanic languages), or its size in relation to smaller gulfs (in Old Latvian), or tribes associated with it (in Old Russian the sea was known as the Varanghian Sea). In modern languages it is known by the equivalents of "East Sea", "West Sea", or "Baltic Sea" in different languages: </P> <Ul> <Li> Baltic Sea is used in English; in the Baltic languages Latvian (Baltijas jūra) (in Old Latvian the Baltic Sea was referred to as "the Big Sea" while the present day Gulf of Riga was referred to as "the Little Sea") and Lithuanian (Baltijos jūra); in Latin (Mare Balticum) and the Romance languages French (Mer Baltique), Italian (Mar Baltico), Portuguese (Mar Báltico), Romanian (Marea Baltică) and Spanish (Mar Báltico); in Greek (Βαλτική Θάλασσα Valtikí Thálassa); in Albanian (Deti Balltik); in Welsh (Môr Baltig); in the Slavic languages Polish (Morze Bałtyckie or Bałtyk), Czech (Baltské moře or Balt), Slovenian (Baltsko morje), Bulgarian (Балтийско море Baltijsko More), Kashubian (Bôłt), Macedonian (Балтичко Море Baltičko More), Ukrainian (Балтійське море Baltijs ′ ke More), Belarusian (Балтыйскае мора Baltyjskaje Mora), Russian (Балтийское море Baltiyskoye More) and Serbo - Croatian (Baltičko more / Балтичко море); in Hungarian (Balti - tenger). </Li> <Li> In Germanic languages, except English, East Sea is used: Afrikaans (Oossee), Danish (Østersøen), Dutch (Oostzee), German (Ostsee), Icelandic and Faroese (Eystrasalt), Norwegian (Østersjøen), and Swedish (Östersjön). In Old English it was known as Ostsæ, in Hungarian the former name was Keleti - tenger (due the German influence). </Li> <Li> In addition, Finnish, a Finnic language, has calqued the Swedish term as Itämeri "East Sea", disregarding the geography (the sea is west of Finland), though understandably since Finland was a part of Sweden from the Middle Ages until 1809 . </Li> <Li> In another Finnic language, Estonian, it is called the West Sea (Läänemeri), with the correct geography (the sea is west of Estonia). </Li> </Ul>

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