Dacian warfare The history of Dacian warfare spans from c . 10th century BC up to the 2nd century AD in the region defined by Ancient Greek and Latin historians as Dacia . It concerns the armed conflicts of the Dacian tribes and their kingdoms in the Balkans . Apart from conflicts between Dacians and neighboring nations and tribes , numerous wars were recorded among Dacians too . Tribal wars . The Dacians fought amongst each other but were later united first under Burebista and later under Decebalus . Despite this after the death of Burebista at 44 BC they had been split by a civil war . Domitian ' s Dacian War . The two punitive expeditions mounted as a border defense against raids of Moesia from Dacia in 86 - 87 AD ordered by the Emperor Titus Flavius Domitianus ( Domitian ) in 87 AD , and 88 AD . The first expedition was an unmitigated disaster , and the second achieved a peace , seen as unfavorable and shameful by many in Rome . Trajan ' s Dacian Wars . Trajan ' s Dacian Wars . The two campaigns of conquest ordered or led by the Emperor Trajan in 101 - 102 AD , and 105 - 106 AD from Moesia across the Danube north into Dacia . Trajan ' s forces were successful in both cases , reducing Dacia to client state status in the first , and taking the territory over in the second . These wars involved no less than 13 legion s . Dacian troop types and organization . Infantry and cavalry . The Dacian tribes were part of the greater Thracian family of peoples . They established a highly militarized society and , during the periods when the tribes were united under one king ( 82 - 44 BC , 86 - 106 AD ) , posed a major threat to the Roman provinces of Lower Danube . Dacia was conquered ( except for the Free Dacians ) and transformed into a Roman province in 106 after a long , hard war . The most important weapon of the Dacian arsenal was the falx . This dreaded weapon , similar to a large sickle , came in two variants : a shorter , one - handed falx called a sica , and a longer two - handed version . The shorter falx was called sica ( sickle ) in the Dacian language . The two - handed falx was a polearm . It consisted of a three - feet long wooden shaft with a long curved iron blade of nearly - equal length attached to the end . The blade was sharpened only on the inside , and was reputed to be devastatingly effective . However , it left its user vulnerable because , being a two - handed weapon , the warrior could not also make use of a shield . Alternatively , it might be used as a hook , pulling away shields and cutting at vulnerable limbs . Using the falx , the Dacian warriors were able to counter the power of the compact , massed Roman formations . During the time of the Roman conquest of Dacia ( 101 - 102 , 105 - 106 ) , legionaries had reinforcing iron straps applied to their helmets . The Romans also introduced the use of leg and arm protectors ( greave s and manica ) as further protection against the falxes . The Dacians were adepts of surprise attacks and skilful , tactical withdrawals using the fortification system . During the wars with the Romans , fought by their last king Decebalus ( 87 - 106 ) , the Dacians almost crushed the Roman garrison s south of the Danube in a surprise attack launched over the frozen river ( winter of 101 - 102 ) . Only the intervention of Emperor Trajan with the main army saved the Romans from a major defeat . But , by 106 , the Dacians were surrounded in their capital Sarmizegetusa . The city was taken after the Romans discovered and destroyed the capital ' s water supply line . Dacians decorated their bodies with tattoos like the Illyrians and the Thracians . The Pannonians north of the Drava had accepted Roman rule out of fear of the Dacians . Dacia remained a Roman province until 271 . Marcus Annaeus Lucanus 39 - 65 wrote of Dacian hordes ; " Have poured her captains , and the troops who guard the northern frontier from the Dacian hordes " Dacians that could afford armor wore customised Phrygian type helmet s with solid crests ( intricately decorated ) , domed helmets and Sarmatian helmets . They fought with spears , javelins , falxes , one - sided battle axes and used " " Draco " " Carnyxes as standards . Most only used shields as a form of defense . Cavalry would be armed with a spear , a long bronze La Tène sword and an oval shield . Most of the infantry would wield a falx and perhaps a sica and would wear no armor at all even shunning shields . Mercenaries . Dacian mercenaries were uncommon in contrast to the Thracians and the Illyrians but they could be found in the service of the Greek Diadochi and of the Romans . Nobility . A 2nd century chieftain would wear a bronze Phrygian type helmet , a corselet of iron scale armor , an oval wooden shield with motifs and wield a sword . Navy . There was no Dacian navy except perhaps boats to cross the Danube . Fortifications . Dacians had built fortresses all around Dacia with most of them being on the Danube . A scene from Trajan ' s column shows Romans attacking a Dacian fortification using the " testudo " . The Dacians constructed stone strongholds , dava s , in the Carpathian Mountains in order to protect their capital Sarmizegetusa . The fortifications were built on a system of circular belts . This allowed the defenders , after a stronghold was lost , to retreat to the next one using hidden escape gates . External influences . Scythian and Sarmatian . The " Dacian Draco " was the standard of the ancient Dacian military . It served as a standard for the Dacians of the La Tene period and its origin must clearly be sought in the art of Asia Minor sometime during the second millennium BC . Sarmatians were part of the Dacian army as allies . The Roxolani became part of the Dacians while the Iazyges fought against them trying to claim their own land . Celtic and Germanic . Celtic iron spear heads and swords from La Tène . Many types of Hallstatt culture and Celtic swords . Wooden shields , sax knives . The Germanic Bastarnae and Germans were an important part of the Dacian army . Celtic weapons were used like long swords and round shields . The Celts played a very active role in Dacia . The Scordisci were among the allies used by the Dacians . Greek and Hellenistic . Cothelas had become a vassal to ancient Macedon . Some Kings of the Getae had been Hellenized Roman . Dacia became a Roman province at 106 AD , and Dacians were eventually Romanized . After their defeat from the Roman a coin called Dacicus was minted by Domitian . Barbarians . Dacians were shown by Trajan as dignified and heroic but still dangerous and unable to stand against the might of Rome . 1st century BC poet Horace writes of them in one of his works and mentions them along with the Scythians as tyrants and fierce barbarians . Later historian Tacitus writes that they are a people that can never be trusted The Ancient Greeks expressed admiration and respect for Burebista . List of Dacian battles . This is a list of battles or conflicts that Dacians had a leading or crucial role in , rarely as mercenaries . They were involved in massive battles against Roman legions .