Decebalus, King Of Dacia
In 43 AD, Claudius invaded Britain, eyeing the island nation as a source for wealth and of course the glory of battles won and expanded Roman territory. It had been a century since Julius Caesar added thousands of miles to the Roman Empire. Claudius got what he never wanted, a massive insurgency. 40 years later, the low-level guerilla war throughout the British Isles was still ongoing, only now Domician was at the helm of the Empire. His brother Titus destroyed the Second Temple and thusly defanged the Jewish insurgency in Israel. Domician definitely lived in his shadow. Titus died suddenly of the plague in 81, and the Praetorian Guard named Domician Emperor.
Like most other Emperors, Domician sought armed combat as a way to advance his own career and status. He invaded Dacia, in modern day this is an area around the Carpathian mountains that stretches from the Danube to the Black Sea. The Dacians were a warlike people who rode well and fought well and had a pretty good steel making capabilities. In fact the Dacians excelled in modern military technology, borrowing and purloining from everyone they came in contact with. Decebalus, who served as their king from 87 to 106 was besting Roman Legions and asserting himself and the Dacian Empire as a sort of minatory empire sitting right next door, just north of the Balkans. This gave them control over access to the Black Sea, the Caspian Sea, parts of the Baltic Sea and of course trade routes into Central Asia. Decebalus knew he was holding a wild card.
Decebalus defeated the Romans twice in 85 AD and 87 AD repulsing Legions led by Cornelius Fuscus, and Tettius Iullianus. Tettius lost more than the war against the Dacians, he lost his Legion standard, the silver eagle. Humiliating Rome and warring on Rome for some barbarians became method for rising into prominence in their own cultures. And at this time, many barbarian tribes had lost their fear of the Romans. Then the Dacians invaded Moesia; they murdered, looted, and plundered in areas bordering Rome. Domician had some success against the Dacians, and that bought him some fame and respect; however he had bigger problems than the Dacians and those problems were at home. He acted with malice towards his relatives or any political rivalries. He intended to munidfy the Senate of any opposition of criticism and in doing so he created his own wall of enemies. His own wife despised him enough to create a ruse, such that Stephanus, his secretary, was fitted with a fake cast. Inside this cast he hid a knife, and when the opportunity was upon him, he killed Domician. Domician was 45 when he died and had served for 15 years. His reign was considered historically as great and mostly peaceful.
In the meantime, timing a revolt across the empire as an advantage, the Germans rebelled. Domician had died in 96 AD and he was replaced by Marcus Cocceius Nerva, a feeble, inarticulate man who engendered no confidence in the Praetorian Guard. Nerva knew he would not survive a coup born in his own guardians, so he took Trajan, the successful warring consul who fought in the administration of Domician and made him his heir and acting warlord. Trajan was a great battlefield general who did more to expand the boundaries of the Empire than anyone previously. Trajan, camping on the Danube, was sent to crush the rebellion. He indeed crushed the Saturnian Rebellion in support of Domician.
The Romans were not a sharing people. Even here in the early middle-ages when the Roman Empire was divided into two, and willing to pay tribute to Barbarians just to keep them from attacking Rome, even at this moment there was a proud and defiant Roman tradition. When Nerva died, Trajan rose to Emperor and set his sights on the Dacians.
Decebalus lived most of his life as a man who defeated Roman armies. He could brag at the end of the day that he established a kingdom next to the Byzantine Roman Empire.
In 101 AD Trajan defeated Decebalus in a massive battle called Second Tapae. The first one was won by the Romans in 88 AD. Decebalus was beginning to dishonor the agreements he made in the First Battle of Tapae. There he was paid a hefty annual tribute and received Roman engineering technology in return for his passivity; but he used the knowledge to help him fortify his positions. In the Battle of Second Tapae, Trajan took 12 Legions across the Danube and create two more on the way with auxilliaries. He and 100,000 Romans made their way to Tapae and faced off against a quarter of a million Dacians. The battle raged for hours until the weather broke. The Dacians took it as a sign to retreat and they egressed the field of battle.
Trajan eventually pursued Decebalus and intended to put his head on a pole to parade it through Rome. Decebalus took his own life instead
The Dacian empire crumbled soon there after.