Based on the archaeological findings, the history of the Triballi can be divided in four periods: Proto-Triballian, Early Triballian, Triballian and period from 335 BC until Roman conquest. In 424 BC, they were attacked by Sitalkes, king of the Odrysae, who was defeated and lost his life in the engagement. They were pushed to the east by the invading Autariatae, an Illyrian tribe; the date of this event is uncertain. In 376 BC, a large band of Triballi under King Hales crossed Mount Haemus and advanced as far as Abdera; they had backing from Maroneia and were preparing to besiege the city when Chabrias appeared off the coast, with the Athenian fleet, and organized a reconciliation. In 339 BC, when Philip II of Macedon was returning from his expedition against the Scythians, the Triballi refused to allow him to pass the Haemus unless they received a share of the booty. Hostilities took place, in which Philip was defeated and wounded by a spear in his right thigh, but the Triballi appear to have been subsequently subdued by him. After the death of Philip, Alexander the Great passed through the lands of the Odrysians in 335-334 BC, crossed the Haemus ranges and after three encounters defeated and drove the Triballians to the junction of the Lyginus at the Danube. 3,000 Triballi were killed, the rest fled. Their king Syrmus took refuge on the Danubian island of Peukê, where most of the remnants of the defeated Thracians were exiled. The successful Macedonian attacks terrorized the tribes around the Danube; the autonomous Thracian tribes sent tributes for peace, Alexander was satisfied with his operations and accepted peace because of his greater wars in Asia. They were attacked by Autariatae and Celts in 295 BC. The punishment inflicted by Ptolemy Keraunos on the Getae, however, induced the Triballi to sue for peace. About 279 BC, a host of Gauls under Cerethrius defeated the Triballi with an army of 3,000 horsemen and 15,000 foot soldiers. The defeat pushed the Triballi further to the east. Nevertheless, they continued to cause trouble to the Roman governors of Macedonia for fifty years. The Illyrian Dardani tribe settled in the southwest of the Triballi area in 87 BC. The Thracian place names survives the Romanization of the region. Pliny the Elder registers them as one of the tribes of Moesia. In the time of Ptolemy, their territory was limited to the district between the Ciabrus and Utus rivers, part of what is now Bulgaria; their chief town was Oescus. Under Tiberius, mention is made of Triballia in Moesia; and the Emperor Maximinus Thrax had been a commander of a squadron of Triballi. The name occurs for the last time during the reign of Diocletian, who dates a letter from Triballis.
The term "Triballians" appears frequently in Byzantine and other European works of the Middle Ages, referring exclusively to Serbs. Some of these authors clearly explain that "Triballian" is synonym to "Serbian". For example, Niketas Choniates in his history about Emperor Ioannes Komnenos: "... Shortly after this, he campaigned against the nation of Triballians ..." or the much later Demetrios Chalkondyles, referring to an Islamized Christian noble: "... This Mahmud, son of Michael, is Triballian, which means Serbian, by his mother, and Greek by his father." or Mehmed the Conqueror when referring to the plundering of Serbia. In the 15th century, a coat of arms of "Tribalia", depicting a wild boar with an arrow pierced through the head, appeared in the supposed Coat of Arms of Emperor Stefan Dušan 'the Mighty'. The motif had, in 1415, been used as the Coat of Arms of the Serbian Despotate and is recalled in one of Stefan Lazarević's personal Seals, according to the paper Сабор у Констанци. Pavao Ritter Vitezović also depicts "Triballia" with the same motif in 1701 and Hristofor Zhefarovich again in 1741. With the beginning of the First Serbian Uprising, the Parliament adopted the Serbian Coat of Arms in 1805, their official seal depicted the heraldic emblems of Serbia and Tribalia. The written sources on the Triballi are scarce but the archaeological remains are abundant. The scientific research of the Triballi was boosted with Fanula Papazoglu's book The Central Balkan Tribes in Pre-Roman Times. Other historians and archaeologists who wrote on the Triballi include, Dragoslav Srejović, Nikola Tasić, Rastko Vasić, Miloš Jevtić and, especially, Milorad Stojić. Even though the two names were used as synonyms by some Byzantine sources and certain heraldic inheritance, Serbian official historiography is not equalizing the Serbs and the Triballi, nor does it fabricate a cultural continuity between the two.
Archaeological findings
Bulgaria
A male grave at Vratsa, with a female thracian suttee. Dated to the 4th century BC, the royal tomb contains beautiful goldwork, like pitchers and wreaths.
Serbia
Archeological findings prove that the Triballi inhabited the Morava Valley region in the Iron Age.
In 2005, several possibly Triballi graves were found at the Hisar Hill in Leskovac, southeastern Serbia.
In June 2008, a Triballi grave was found together with ceramics in Požarevac, central-eastern Serbia.
Triballi tomb unearthed at Ljuljaci, west of Kragujevac, central Serbia.
