Instances of Thracian people engaging in armed conflict occur in the Iliad of Homer and in Greek mythology.
[3] The Thracians were a particularly fierce culture in terms of violence and conflict and so they appeared in Greek Mythology as mostly associated with its stories of strife.
Homer recounts in the book of Odyssey that an embarrassed Ares retreated among his Thracian followers when his love affair with the goddess Aphrodite was caught and the two were promptly ensnared by Hephaestus.
[5] The tribal wars also kept Thrace from becoming a major regional power due to the lack of a central government.
[6] At the onset of the Peloponnesian War, the Thracian tribes were united under the rule of Sitalces, king of the Odrysae.
It became involved in wars and military conflicts against the Romans, Greek colonies, the kingdom of Macedon and the Diadochi, the Persian Empire, Paeonians, Dacians, Celts,[9] Scythians and Thracian tribes.
[12] Odrysian military strength was based on intra-tribal elite[13] making the kingdom prone to fragmentation.
Although the kingdom was wealthy, a large proportion of its income was in kind and suitable portions had to be paid to the tribal chiefs.
[14] The Thracians fought as peltasts using javelins and crescent[15] or round wicker shields called peltes.
Thracians shunned armor and greaves and fought as light as possible, favoring mobility above all other traits and had excellent horsemen.
[19] The Bithynian Thracians had contributed a number of 6,000 men (60,000 according to Herodotus) in Xerxes I of Persia campaign of 480 BC but in general resisted Persian occupation and turned against Mardonius's army as he retreated.
[26] In the 4th century BC, both infantry and cavalry troops started wearing helmets[27] (some of leather)[28] and some peltasts are seen with greaves.
[29] Armor, when it was available (for the nobility), was at first leather or bronze but iron armour started appearing in the 4th century BC.
[34] It was also legendary for its combat power so that Philip of Macedon adopted its wedge-shaped formation for the Macedonian cavalry maneuvers.
[27] Thracians were highly[38] sought as mercenaries due to their ferocity in battle,[14] but they were infamous for their love of plunder.
[23] In one instance in 413 BC, Dii mercenaries were so expensive to pay that after they missed the boat to Sicily the Athenians sent them home.
They later formed one of the most important nationalities in the Roman army, contributing up to 20,000 troops at any one time to auxiliary units during the early empire.
One could be equipped with a Chalcidian type helmet,[23] a breastplate (this sort of armor is rarely found outside Crete[41] and only one has been found in Thrace, a bell-type[42] cuirass) with a mitrai (a plate attached to the bottom of the cuirass to protect the abdomen[43]), a wicker pelte, two javelins and a sword.
The royal name Spartokos (Spartacus) is shared between some Thracian royalty and some Crimean Skythian kings.
Thracian warfare was affected by Celts[20] in a variety of ways like the adoption of certain long swords though this must not have been universal among them.
Greece[52] affected Thracian warfare early on with the xiphos[53] and other swords, Greek type greaves, breastplates, a variety of helmets and other equipment.
[20] The Dii[66] were responsible for the worst atrocities[23] of the Peloponnesian war killing every living thing, including children and dogs, in Tanagra and Mycalessos.