The arrival of the Flavian dynasty, in particular the accession of the emperor Domitian, saw an escalation in the level of conflict along the lower and middle Danube. In approximately 84 or 85 AD the Dacians, led by King Decebalus, crossed the Danube into Moesia, wreaking havoc and killing the Moesian governor Gaius Oppius Sabinus. Domitian responded by reorganising Moesia into Moesia Inferior and Moesia Superior and launching a war against Decebalus. Unable to finish the war due to troubles on the German frontier, Domitian concluded a treaty with the Dacians that was heavily criticized at the time. This would serve as a precedent to the emperor Trajan's wars of conquest in Dacia. Trajan led the Roman legions across the Danube, penetrating Dacia and focusing on the important area around the Orăștie Mountains. In 102, after a series of engagements, negotiations led to a peace settlement where Decebalus agreed to demolish his forts while allowing the presence of a Roman garrison at Sarmizegetusa Regia (Grădiștea Muncelului, Romania) to ensure Dacian compliance with the treaty. Trajan also ordered his engineer, Apollodorus of Damascus, to design and build a bridge across the Danube at Drobeta.