The Dacian Wars ( 101–102 , 105–106 ) were two military campaigns fought Hostile_encounter between the Roman Empire and Dacia during Emperor Trajan 's rule .

Trajan turned Change his attention to Dacia , an area north of Macedon and Greece and east of the Danube that had been on the Roman agenda since before the days of Caesar when the Dacians defeated Conquering a Roman army at the Battle of Histria .

Emperor Trajan recommenced Process_start hostilities against Dacia and , following an uncertain number of battles , defeated Conquering the Dacian king Decebalus in the Second Battle of Tapae in 101 .

In response Trajan again marched Self_motion into Dacia , besieging Besieging the Dacian capital in the Siege of Sarmizegetusa , and razing Destroying it .

With Dacia quelled , Trajan subsequently invaded Attack the Parthian empire to the east , his conquests expanding Expansion the Roman Empire to its greatest extent .