Venethi

The term Vistula Veneti (or Baltic Veneti) has been used in modern times to distinguish the Veneti noted by Greek and Roman geographers along the Vistula and the Bay of Gdańsk from other tribes around them and other tribes of the same name elsewhere such as the Adriatic Veneti (about the same area of today's Veneto), the Veneti of Brittany, and the so-called Paphlagonian Veneti (of today's northern Turkey coast). They are one of the tribes that are suspected as the ancestors of some or all of today's Slavs.

Roman authors saw the lands between the Rhine and the Vistula rivers as Germania. East of the Vistula was classed as Sarmatia. The earliest source that refers to Veneti in Central Europe as the "Vennones" and as members of the "Vindelici" is from Strabo, locating them, at the turn of the millennium, north of Italy along Lake Constance (previously known as Lake Veneti), recalling a campaign and a lake battle conducted against them by Drusus and Tiberius. He also speculates that the Veneti may have settled in Venice and migrated north into Italy.Pliny the Elder places the Veneti along the Baltic coast. He calls them the Sarmatian Venedi (Latin Sarmatae Venedi). Thereafter, the 2nd-century Greek-Roman geographer Ptolemy, in his section on Sarmatia, places the Greater Vouenedai along the entire Venedic Bay, which can be located from the context on the southern shores of the Baltic. He names tribes south of these Greater Venedae both along the eastern bank of the Vistula and further east.

The most exhaustive Roman treatment of the Veneti comes in Germania by Tacitus, who, writing in AD 98, locates the Veneti among the peoples on the eastern fringe of Germania. He was uncertain of their ethnic identity, classifying them as Germans based on their way of life but not based on their language (in comparison to, for example, the Peucini):

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