The first triumvirate was a coalition between Gaius Julius Caesar, Gnaeus Pompeius and Crassus. It was created as a counter to the senate group of the boni, which were against anything that changed the republic. Look up the part of the roman empire that talks about it. It pretty much made it possible for caesar to stay in Gaul and bring them under Roman influence. After Crassus's death in Parthia, Pompey and Caesar stayed allied because of Pompey being married to Caesar's daughter. after Caesars daughter died, the Boni went to Pompey to try to pull him away from Caesar so they could prosecute him after he returned.