Proto-history
In 98 AD Tacitus described one of the tribes living near the Baltic Sea (Mare Svebicum) as Aestiorum gentes and amber gatherers. It is believed that these peoples were inhabitants of the Sambian peninsula, although no other contemporary sources exist.
This homeland includes all historical Balts, and every location where Balts are thought to have been at different periods in time. Over time, the huge area of Baltic habitation shrank, due to assimilation by other groups, and invasions. According to one of the theories which has gained considerable traction over the years, one of the western Baltic tribes, Galindians, Galindae, or Goliad, migrated to the Eastern end of Baltic realm around the 4th century AD, and settled around modern day Moscow, Russia. Finally, according to Slavic chronicles of the time, they warred with Slavs, and perhaps, were defeated and assimilated some time in 11-13 centuries.
Balts became differentiated into Western and Eastern Balts in the late centuries BC. The eastern Baltic region was inhabited by ancestors of Western Balts - Old Prussians, Sudovians/Jotvingians, Scalvians, Nadruvians, and Curonians. Meanwhile, Eastern Balts were living in modern day Belarus, Ukraine and Russia. Subsequent Germanic and Gothic domination in the first half of the first millennium AD in Northern and Eastern Europe, as well as later Slavic expansion, caused large migrations of the Balts — first, Galindae or Galindians to the east, and later, Eastern Balts to the west — until they reached the ethnographic area of the Balts as we know it, since 13th and 14th centuries. Many other Eastern and Southern Balts either assimilated with other Balts, or contributed to the formation of the Slavs in the 4th-7th centuries, and were gradually slavicized.
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