Ancient history of Transylvania

In ancient times, Romans exploited the gold mines in what is now Transylvania extensively, building access roads and forts to protect them, like Abrud. The region developed a strong infrastructure and economy, based on agriculture, cattle farming and mining. Colonists from Thracia, Moesia, Macedonia, Gaul, Syria, and other Roman provinces were brought in to settle the land, developing cities like Apulum (now Alba Iulia) and Napoca (now Cluj Napoca) into municipiums and colonias.

The Dacians rebelled frequently, the biggest rebellion occurring after the death of emperor Trajan. Sarmatians and Burs were allowed to settle inside Dacia Trajana after repeated clashes with the Roman administration. During the 3rd century increasing pressure from the free Dacians (Carpians) and Visigoths forced the Romans to abandon exposed Dacia Trajana.

In 271, the Roman emperor Aurelian abandoned Dacia Trajana and reorganised a new Dacia Aureliana inside former Moesia Superior. The abandonment of Dacia Trajana by the Romans is mentioned by Eutropius in his Breviarium Liber Nonus.

The province of Dacia, which Trajan had formed beyond the Danube, he gave up, despairing, after all Illyricum and Moesia had been depopulated, of being able to retain it. The Roman citizens, removed from the town and lands of Dacia, he settled in the interior of Moesia, calling that Dacia which now divides the two Moesiae, and which is on the right hand of the Danube as it runs to the sea, whereas Dacia was previously on the left.

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