The next step towards the imposition of direct control of Asia Minor was achieved when the realm of Pergamon was ceded by testament to Rome following the death of Attalos III in 133 BC. In spite of lingering doubts, even on the Roman side, the scope of Roman rule expanded still further in the following period, and already by 64 BC large parts of Asia Minor had fallen under Roman sway, following the reorganization of Pompeius. All this was preceded by the wars of Pontos, ruled by Mithradates VI, which marked the final attempt by a power of Asia Minor to launch offensive operations against Rome. In addition to districts which were administered by the Roman authorities as provinces, Rome continued to rely on dependent local rulers, in order to secure peace and stability in Asia Minor. This led to an increasing emphasis on security measures against the realm of the Parthians to the east. The unstable fortunes of individual client princes led to frequent territorial shifts, which could also affect the Roman provinces. It was only under Vespasian that the last of these client states were dissolved and turned into Roman provinces. With this, all of Asia Minor passed under direct Roman control. Until Diocletian's thorough reorganization, there were only few changes in the borders of these provinces.