Explanation: The three men pictured and named were the three members of the First Triuumvirate, a political alliance of the Late Republic which concentrated political power into the hands of the three men, who had clawed their ways upwards in the world - whether through obscene wealth (Crassus), military exploits (Pompey), or skilled politiking (Caesar) rather than the strength of their family names and connections. All three men were thus opposed strongly by the optimates - the aristocratic faction of the Late Republic, though of the three men, only Caesar was a longtime populare, a member of the faction of the poor. This alliance allowed the three men, all holding powerful offices, to push through various measures, many self-serving, some ideological, which otherwise would have been blocked by the normal functions of the Senate and Assemblies.
After Crassus's untimely death in the favorite Roman pastime of 'failing to conquer Persia', Pompey and Caesar became estranged, and Pompey eventually sided with the Senatorial aristocracy against Caesar in the ensuing civil war.