The Bessi (//; Ancient Greek: Βῆσσοι, Bēssoi or Βέσσοι, Béssoi) were an independent Thracian tribe who lived in a territory ranging from Moesia to Mount Rhodope in Northern Thrace, but are often mentioned as dwelling about Haemus, the mountain range that separates Moesia from Thrace and from Mount Rhodope to the northern part of Hebrus.
Herodotus described them as a sort of priestly-caste among the Satrae, the Bessi being interpreters of the prophetic utterances given by a priestess in an oracular shrine of Dionysus located on a mountain-top. In 72 BC, the proconsul of Macedonia Marcus Terentius Varro Lucullus defeated the Bessi in Thrace. Later Strabo, provides a record in which the Bessi are described as the fiercest of the independent Thracian tribes, dwelling on and around the Haemus range, and possessing the greater part of the area around that mountain chain. He calls them brigands among brigands and that they were addicted to plunder. Mommsen says the capital of the Bessi was Uscudama (now Edirne) in modern Turkey but the real place seems to have been Bessapara, today Sinitovo near Pazardzhik, Bulgaria. The Diobesi are thought to be a union of sorts between the Besai and the Dii. Pliny the Elder reveals that there were several divisions of the Bessi.
Appian writes that they fearfully surrendered to Augustus. Towards the end of the 4th century, Nicetas the Bishop of Dacia brought the gospel to "those mountain wolves", the Bessi. Reportedly his mission was successful, and the worship of Dionysus and other Thracian gods was eventually replaced by Christianity. A Thracian personal name Bessus (attested in Northern Montenegro along with other Thracian names such as Teres) is considered to have the same etymon as Bessi (Wilkes, 1982). In the 11th century Strategikon text, Cecaumenos the Byzantine historian described the Vlachs from Thessaly (i.,e. the Aromanians of Great Wallachia) as being descendants of ancient Dacians and Bessi who invaded Greece from the area on the Danube, supposedly seeking revenge for the defeat inflicted to their ancestors by Trajan during the Dacian Wars.
In 570, Antoninus Placentius wrote that in the valleys of Mount Sinai there was a monastery in which the monks spoke Greek, Latin, Syriac, Egyptian and Bessian. The origin of the monasteries is explained in a mediaeval hagiography written by Simeon Metaphrastes, in Vita Sancti Theodosii Coenobiarchae in which he wrote that Saint Theodosius founded on the shore of the Dead Sea a monastery with four churches, in each being spoken a different language, among which Bessan was found. The place where the monasteries were founded was called "Cutila", which may be a Thracian name.
Further fate of the Bessi is a matter of dispute. Some authors like Gottfried Schramm derived the Albanians from the Christianized Bessi, after their remnants were pushed by Slavs and Bulgars during the 9th century westwards into today Albania, while mainstream historians support Illyrian-Albanian relation.
- Harry Thurston Peck, Harpers Dictionary of Classical Antiquities (1898),"(Bessoi). A people of Thrace dwelling in a district known as Bessica, between Mount Rhodopé and the northern part of the river Hebrus."
- Herodotus, The Histories,7.111.1,"CXI. The Satrae, as far as we know, have never yet been subject to any man; they alone of the Thracians have continued living in freedom to this day; they dwell on high mountains covered with forests of all kinds and snow, and they are excellent warriors.  It is they who possess the place of divination sacred to Dionysus. This place is in their highest mountains; the Bessi, a clan of the Satrae, are the prophets of the shrine; there is a priestess who utters the oracle, as at Delphi; it is no more complicated here than there.1 ,Hdt. appears to mean that the method of divination is the "usual" one, as at Delphi; perhaps there were exaggerated accounts of the mysterious rites of the Bessi."
- Plin. Nat. 4.18,"Thrace now follows, divided into fifty strategies1, and to be reckoned among the most powerful nations of Europe. Among its peoples whom we ought not to omit to name are the Denseletæ and the Medi, dwelling upon the right bank of the Strymon, and joining up to the Bisaltæ above2 mentioned; on the left there are the Digerri and a number of tribes of the Bessi"
- The Thracians 700 BC-AD 46 (Men-at-Arms) by Christopher Webber and Angus McBride,ISBN 1-84176-329-2, 2001, page 15: "... of the Emperor Augustus) who returned the favour, defeating the Bessi when they attacked Macedonia. This tribe must have impressed the Romans, as they took to calling all Thracians `Bessi'; they wrote it down as the tribe of origin ..."
- Strabo, Geography,Strab. 7.5,"Then come the peoples who live in the neighborhood of the Haemus Mountain and those who live at its base and extend as far as the Pontus—I mean the Coralli, the Bessi, and some of the Medi92 and Dantheletae. Now these tribes are very brigandish themselves, but the Bessi, who inhabit the greater part of the Haemus Mountain, are called brigands even by the brigands. The Bessi live in huts and lead a wretched life; and their country borders on Mount Rhodope, on the country of the Paeonians, and on that of two Illyrian peoples—the Autariatae, and the Dardanians."
- The History of Rome, Volume 4 by Theodor Mommsen , 2009, page 53: "... defeated the Bessi in their mountains, took their capital Uscudama (Adrianople), and compelled them to submit to the Roman supremacy
- The Cambridge Ancient History, Volume 3, Part 2: The Assyrian and Babylonian Empires and Other States of the Near East, from the Eighth to the Sixth Centuries BC by John Boardman, I. E. S. Edwards, E. Sollberger, and N. G. L. Hammond ,ISBN 0-521-22717-8,1992,page 607: "The existence of a tribe called Diobessi (Plin.Loc.Cit.) links together ethnically the Bessi and the Dii"
- Pliny the Elder, The Natural History,4.18,"Thrace now follows, divided into fifty strategies1, and to be reckoned among the most powerful nations of Europe. Among its peoples whom we ought not to omit to name are the Denseletæ and the Medi, dwelling upon the right bank of the Strymon, and joining up to the Bisaltæ above2 mentioned; on the left there are the Digerri and a number of tribes of the Bessi3, with various names, as far as the river Mestus4, which winds around the foot of Mount Pan- gæum5, passing among the Elethi, the Diobessi6, the Carbilesi; and then the Brysæ, the Sapæi, and the Odomanti."
- Appian, Illyrian Wars,Horace White, Ed.,App. Ill. 4," From these tribes he exacted the tributes they had been failing to pay. When these were conquered, the Hippasini and the Bessi, neighboring tribes, were overcome by fear and surrendered themselves to him"
- 1994 Gottfried Schramm: A New Approach to Albanian History
- Indo-European language and culture: an introduction By Benjamin W. Fortson Edition: 5, illustrated Published by Wiley-Blackwell, 2004 ISBN 1-4051-0316-7, ISBN 978-1-4051-0316-9
- Stipčević, Alexander. Iliri (2nd edition). Zagreb, 1989 (also published in Italian as "Gli Illiri")
- NGL Hammond The Relations of Illyrian Albania with the Greeks and the Romans. In Perspectives on Albania, edited by Tom Winnifrith, St. Martin's Press, New York 1992
- "Johann Thunmann: On the History and Language of the Albanians and Vlachs"
- (in Romanian) Lozovan, Eugen, Dacia Sacră, Editura Saeculum, București, 2005.
- (in French) Peeters, Paul, "La version ibéro-arménienne de l'autobiographie de Denys l'Aréopagite", Analecta Bollandiana 39, 1921, p. 288-290.
- Wilkes, John, The Illyrians, 1982, p. 84.