his first campaign (101–102) was the siege of the Dacian capital Sarmizegethusa and the occupation of part of the country. Emperor Trajan recommenced hostilities against Dacia and, following an uncertain number of battles, and with Trajan's troops pressing towards the Dacian capital Sarmizegethusa, Decebalus once more sought terms. Decebalus rebuilt his power over the following years and attacked Roman garrisons again in AD 105. In response Trajan again marched into Dacia, attacking the Dacian capital in the siege of Sarmizegethusa, and razing it to the ground, the defeated Dacian king Decebalus committed suicide to avoid capture. In the following years, a new city was built on the ruins of the Dacian capital named Ulpia Traiana Sarmizegetusa. With part of Dacia quelled as the Roman province Dacia Traiana. Trajan subsequently invaded the Parthian empire to the east. His conquests brought the Roman Empire to its greatest extent. Rome's borders in the east were governed indirectly in this period, through a system of client states, which led to less direct campaigning than in the west. The weapon most associated with the Dacian forces that fought against Trajan's army during his invasions of Dacia was the falx, a single-edged scythe-like weapon. The falx was able to inflict horrible wounds on opponents, easily disabling or killing the heavily armored Roman legionaries that they faced. This weapon, more so than any other single factor, forced the Roman army to adopt previously unused or modified equipment to suit the conditions on the Dacian battlefield. Some of the history of the war is given by Cassius Dio. Trajan erected the Column of Trajan in Rome to commemorate his victory. Roman Dacia (106–275 AD) Roman Dacia, also known as Dacia Felix, was organized as an imperial province on the borders of the empire. It is estimated that the population of Roman Dacia ranged from 650,000 to 1,200,000. The area was the focus of a massive Roman colonization. New mines were opened and ore extraction intensified, while agriculture, stock breeding, and commerce flourished in the province. Roman Dacia was of great importance to the military stationed throughout the Balkans and became an urban province, with about ten cities known and all of them originating from old military camps. Eight of these held the highest rank of colonia. Ulpia Traiana Sarmizegetusa was the financial, religious, and legislative center and where the imperial procurator (finance officer) had his seat, while Apulum