From JoanK:
The first thing I thought when I read Pompey was WHAT ON EARTH is all this fighting about?
I looked in my copy of Story of Civilization to get a feel for the times when Pompey lived. At that time, Rome ruled all of Italy, and in addition was conquering neighboring areas. There were three areas of tension that an ambitious soldier could use to his advantage to gain wealth, glory and/or power.
First, Rome's wealth depended on capturing new lands, bringing back wealth and slaves to sustain Rome.
Second, Italians outside of Rome were resentful of Rome's power. While they didn't rebel during this period, a Roman who had been expelled from Rome could go to another Roman town and raise an army, promising future favors.
Third, within Rome, itself, the government was supposed to provide a balance between the Patricians (descendents of the oldest families) and the Plebes (all the other citizens). But in fact, the patricians ruled the roost. The Plebes resented this, and if someone wanted to seize (or keep) power in Rome, he could get the backing of the Plebes by promising concessions.
The men with armies oftened combined these missions. A man might raise an army to go and fight a rebellion, while he was there, going on to conquer new lands for Rome. When he came back to Rome, he was supposed to disband his army and enter Rome in peace. Sometimes that happened, and sometimes he was honored and offered a position of power. But If he had enemies in Rome, another army might be sent out to meet him, with the winner getting the power.
This sort of thing seemed to happen in Pompey's lifetime, not once or twice but again and again. You can't always tell reading Plutarch exactly what's going on, since he assumes we know who all the people are. But I don't think we have to know in detail about each battle, as long as we understand the thrust. A lot of conquering of non-Romans, combined with a lot of power struggles between Romans (indeed between Patricians) with no wider aim than to change which of them was at the top of the heap.
Indeed, although some of these fights involved promises of change to plebes or Italians, in fact, there was no fundemental change involved. These civil wars are not comparable to ours, or to the revolution, say, where fundemental structural changes resulted.
