Yotvingians, or Sudovians (also called Suduvians, Jatvians, or Jatvingians in English; Lithuanian: Jotvingiai, S?duviai; Latvian: J?tvingi; Polish: Ja?wingowie, Belarusian: , German: Sudauer), were a Baltic people with close cultural ties in the 13th century to the Lithuanians and Prussians. The Yotvingian language (sometimes called Sudovian) was a Western Baltic language, nearest to Old Prussian but with small variations. They were referred to in regional historical records into the 19th century.
The Yotvingian lived in the area of Sudovia (Yotvingia) and Dainava, southwest from the upper Neman (Nemunas). Today this area corresponds mostly to the Podlaskie Voivodeship of Poland, portions of Lithuania and a part of Hrodna Province of Belarus. The territory was between later the Marijampol? and Merkin? (Lithuania); Slonim and Kobryn (Belarus); and Bia?ystok, and Lyck,in Prussia now E?k (Poland).
The name S?duva, according to Vytautas Ma?iulis ("Pr?s? kalbos etimologijos ?odynas", Etymological Dictionary of the Prussian Language), derives from a local hydronym *S?d(a)v?, in turn derived from a Baltic verbal root *s?-: to flow, pour.
A. S. Kibin proposed Yotvingian, or the "Slavic Jatviagi as the group name goes back to O. N. patronymic derivative játvingar meaning « the descendants of Játvígr », or « the people of Játvígr »" - "the name Játvígr mentioned by Knytlinga saga". J. Pashka, acknowledging Kibin's proposal, has similarly interpreted the ethnonym as derived from the Old Norse Játvígr, with a genitive Játvígs liðsmenn ( ? ? ) label of Játvígr's Viking expedition and his Norse Rus' settlers ( i.e. Indura, Belarus ) by the Nemunas river. Pashka asserts the nasal infixation in the original Old Norse Játvíg name of the 944-945 Kiev Treaty was probably an insignificant scribal error or misinterpretation, that has survived to the present.
According to The Histories of Herodotus (5th century B.C.), the Neuri were a tribe living beyond the Scythian cultivators, one of the nations along the course of the river Hypanis (Bug river), west of the Borysthenes (Dniepr river). This was roughly the area of modern Belarus and Eastern Poland by the Narew river, coinciding with the Yotvingian linguistic territory of toponyms and hydronyms (Narew river).
In 944, during the treaty between the Kievan Rus' prince Igor and the emperor of the Byzantine Empire, the Yotvingians were hired by the Kievan ruler to serve as mercenaries. Also Vladimir I of Kiev, in 983, hired the Yotvingians to add to his army.
Ptolemy in the 2nd century AD called the people Galindai kai Soudinoi (). Peter von Dusburg called them Galindite and Suduwite. In the Hypatian Codex the spellings are changing: Jatviagy, Jatviezie, Jatvia?in, zemlia Jatveskaja, na zemliu Jatvia?s´kuju and more. Polish sources also used Russian spellings: Jazviagi, Iazvizite, Jazvizite, Yazvizite. In the treaty with the Teutonic Knights in 1260, the region is called "terre Getuizintarum". This name was taken by the papal administration: terra Jatwesouie, Gretuesia, Gzestuesie, Getuesia und Getvesia. The Knights called this tribe Sudowite, Sudowia, in qua Sudowit.
In the sentence of Breslau of the emperor Sigismund of Luxembourg to the Order of Livland from 1325, this area is called Suderlandt alias Jetuen. In two dotations (1253 and 1259) of Mindaugas I, a new name was recorded: Dainava, Deynowe, Dainowe, Denowe (land of songs). The forests were named Deinova Jatve?.
Yotvingians also had a strong warrior culture and were generally well known as great warriors and hunters, and were feared by their neighbours for their skill in warfare. Skalmantas, leader of the Yotvingians was responsible for single-handedly raiding Pinsk in the Principality of Turov.
A census by the clergy of the Belarus Grodno area in 1860 had as many as 30,929 inhabitants identifying as Yatviags.