soon began to rearm, to again harbour Roman runaways, and to pressure his Western neighbours, the Iazyges Sarmatians, into allying themselves with him. Through his efforts to develop an anti-Roman bloc, Decebalus prevented Trajan from treating Dacia as a protectorate instead of an outright conquest. In 104, Decebalus devised an attempt on Trajan's life by means of some Roman deserters, a plan that failed. Decebalus also took prisoner Trajan's legate Longinus, who eventually poisoned himself while in custody. Finally, in 105, Decebalus undertook an invasion of Roman-occupied territory north of the Danube. Prior to the campaign, Trajan had raised two entirely new legions: II Traianawhich, however, may have been posted in the East, at the Syrian port of Laodiceaand XXX Ulpia Victrix, which was posted to Brigetio, in Pannonia. By 105, the concentration of Roman troops assembled in the middle and lower Danube amounted to fourteen legions (up from nine in 101)about half of the entire Roman army. Even after the Dacian wars, the Danube frontier would permanently replace the Rhine as the main military axis of the Roman Empire. Including auxiliaries, the number of Roman troops engaged on both campaigns was between 150,000 and 175,000, while Decebalus could dispose of up to 200,000. Other estimates for the Roman forces involved in Trajan's second Dacian War cite around 86,000 for active campaigning with large reserves retained in the proximal provinces, and potentially much lower numbers around 50,000 for Decebalus' depleted forces and absent allies. In a fierce campaign that seems to have consisted mostly of static warfare, the Dacians, devoid of manoeuvring room, kept to their network of fortresses, which the Romans sought systematically to storm (see also Second Dacian War). The Romans gradually tightened their grip around Decebalus' stronghold in Sarmizegetusa Regia, which they finally took and destroyed. A controversial scene on Trajan's column just before the fall of Sarmizegetusa Regia suggests that Decebalus may have offered poison to his remaining men as an alternative option to capture or death while trying to flee the besieged capital with him. Decebalus fled but, when later cornered by Roman cavalry, committed suicide. His severed head, brought to Trajan by the cavalryman Tiberius Claudius Maximus, was later exhibited in Rome on the steps leading up to the Capitol and thrown on the Gemonian stairs. The famous Dacian treasures were not found in the captured capital and their whereabouts were only revealed when