Why were the Roman senators feel threatened by Roman generals?

Answer 1

It was during thew period of the late Republic, after the Marian reforms of the army, that Roman military commanders could be a threat to the senate. Prior to the reforms, the Roman army was a part-time militia of drafted peasant farmers. The soldiers were levied for the military campaigning season and then went back to their farms. There was a property threshold to join the army because the soldiers had to procure and pay for their military equipment themselves. Gaius Marius abolished the property threshold, made joining the army voluntary and provided that the soldiers were to receive their military equipment for free. After 16 years of service they were to be given the grant of a plot of land to farm. The landless poor flocked to the army, which they saw as an institution which would take care of them, and give them a pay and a sort of person. However, a centralised system of recruitment was not established and soldiers were often recruited and paid by the military commanders. This made them loyal to their commanders. Soldiers were recruited by commanders involved in civil wars. They loyalty of soldiers could be used by their commanders to obtain what they wanted. . An example of this was in 71 BC Crassus and Pompey camped their troops outside Rome to put pressure have themselves elected as consuls (the two annually elected heads of the Republic). Pompey was not even eligible on the grounds of being below the required age and of not having served some public offices which were required before the consulship.

During the military anarchy of the crisis of the 3rd century it was the emperors who were threatened by military commanders. There were commanders who were hailed as emperors by their own troops and deposed the incumbent emperor. During the period of rule by emperors the emperors were absolute rulers and the senate had little power.