And so, in keeping with my obsession with how democracies fail, I will start addressing First Man in Rome in that light. Colleen McCullough starts her series with Gaius Marius. This is a reasonable choice if the series is supposed to focus on Julius Caesar as its hero. Marius was married to Caesar's aunt, and their association played a major role in shaping his career. Caesar's parents meet, marry, and set up a household in the novel, and he has just been born when it ends.
On the other hand, if the series is supposed to be about the fall of the Roman Republic, then it really ought to start with the Gracchi brothers. The Gracchi brothers sought to reverse the baleful power of R > G. While Rome was once a land of smallholder farmers, it had increasingly become a land of vast slave plantations with the small holders reduced to an unemployed urban rabble. The Gracchi sought to reverse this trend by making land available to the urban poor. In this, they ran into fierce resistance from the great land holders, violence broke out, the Gracchi were killed, their followers crushed, and a bloody crackdown followed. These were events within living memory at the time of First Man in Rome and cast a shadow on everything that happens in the novel. To the Senatorial elite, the Gracchi were the embodiment of a wild-eyed radicalism to be avoided at all costs. To the broader public, the Gracchi were heroes. By coming in later in events, McCullough avoids having to take sides and make any realistic assessment of the Gracchi. However, as she acknowledges, it was with the Gracchi that the slow unwinding of the Republic began. This is not to blame them for it. After all, R > G had been undermining the Republic for some time, and, as countless T-shirts and bumper stickers proclaim, they only call it class warfare when we fight back.
Events start about 13 years later with the rise of Marius. Marius' enemies call him a "peasant." More accurately, he starts out as a country squire, a big fish in a small pond and comes to Rome to find himself a small fish in a big pond. He comes from a non-Roman part of Italy, one that has been granted Roman citizenship, but that older Romans look down upon as not a real "Roman of the Romans." Part of Marius' reputation as a radical no doubt comes from his outsider status -- not being part of Rome's ruling circles, he is constantly in danger of transgressing against some cherished tradition without meaning to, simply because he does not understand that it is a cherished tradition.
Part of his reputation as a radical comes from the reforms he is undertaking and his failure to understand their full ramifications. Marius is portrayed as an old soldier who comes rather late into a political career, as not as wanting to upturn Rome's social order, but simply as wanting to introduce military reforms that will improve the operation of its army, not understanding their far-reaching effect on the social order. Before the time of Marius, Roman soldiers were recruited from its small property holders and required to provide their own arms. This arrangement was becoming less and less workable for a variety of reasons. For one, not much emphasized in the novel, the numbers of small property holders was shrinking as more and more were squeezed out and became urban unemployed. For another, that was emphasized, constant wars drawn from a dwindling number of recruits meant that Rome was running out of men eligible to serve. And another, that received intermediate attention, was that having citizen-soldiers leave their small properties to fight and then return worked reasonably well when Rome was small and fighting was limited to the Italian peninsula. By Marius' time, Rome had expanded to a mighty empire and war often meant overseas campaigns of many years. This, in turn, meant that small property holders were not able to attend to their small properties and tended to become impoverished as a result of the wars and end up propertlyless and unemployed.
What Marius proposed, then, was to recruit from the urban unemployed without property -- the Head Count.* They would be provided standardized equipment at the expense of the state and receive standardized training. McCullough discusses the advantage of standardized training and equipment in military efficacy. Another advantage to recruiting men with no military background was that Marius could break some cherished but outdated military tradition without meeting resistance from his troops. A disadvantage was the low rate of literacy in his army, and good communications are, after all, a vital component of military effectiveness.
One can see other, far-reaching effects of such an army that McCullough does not discuss. It offered men hitherto despised as rabble, good only for producing offspring, a career and self-respect. It reduced the pressure on Rome's small property holders. It raised taxes, as the state now had to pay for gear for a large force. On the other hand, by recruiting from the unemployed, such an army did not reduce the productive members of society and presumably increased the tax burden that could be born. And (one may speculate) by sending away Rome's poorest, unemployed, undisciplined men of fighting age, it probably cut down on the crime rate. Wikipedia also notes a huge advantage that, by creating a standing army, Marius saved Rome from having to raise and train a fighting force after a military emergency arose.
But Marius' army also created a huge problem -- what to do with his soldiers after the fighting was over. After all, unleashing a group of men with no property, no civilian work history, no future and no hope, but plenty of military training and discipline on Rome is not a prospect anyone would want to contemplate.** Marius' solution is to give his soldiers land in the conquered areas. This raises the specter of the Gracchi brothers and scares the hell out of the ruling class, even as Marius argues that, he differs from the Gracchi in two important aspects: He is not giving away land for free, but only to men who earn it in service to their country, and he is not giving away land in Italy, but land in conquered areas. These arguments, plus perhaps the fear of what would happen if Marius' soldiers don't get land, ends up convincing Rome's rulers. His soldiers get their land.
The Wikipedia notes that this ended up having two far-ranging effects, for good and for ill. On the plus side, settling these veterans in far-flung Roman provinces tended to assimilate and Romanize all parts of the empire, reducing the risk of unrest and revolt. On the minus side, it made soldiers loyal to their individual general, rather than the Roman state and started the undermining of the Republic. It seems most unlikely that anyone in Marius' time would have foreseen either of these outcomes. Nonetheless, McCullough portrays foresightful people as recognizing both the promise and the danger. Marius describes the tendency of his soldiers to form colonies and assimilate the areas where they settle as a positive -- it reduces danger of unrest by Romanizing the entire empire. Conservative forces are outraged and see their Roman-ness as a precious quality to be held closely and not shared with outsiders. Some of his friends, in turn, see the possible danger in the power the he could have in dispensing so much land to so many followers. They say that the danger could be avoided by arranging for the state to give such a land grant to all retired veterans as a matter of routine.***
Finally, the novel establishes that Marius is no true radical and is loyal to the Republic when a real radical becomes a demagogue of the lowest order -- making unrealistic promises about cheap grain in time of famine that he is unable to keep, and then touching off a revolt when the promises are not kept. Faced with the real danger of revolt to the Republic, Marius and his conservative foes join forces, the conservatives not hesitating to give him emergency powers to suppress the revolt, which he sorrowfully does, using minimum force. Shipments of grain come in, and Marius promises cheap prices for the next 19 days of his consulship, leaving to his successor what to do after. Of course, he knows that his successor will have to continue providing cheap grain or face all-out revolt. Having then served an unprecedented six terms as consult and an unprecedented five right in a row, Marius retires. The ending seems happy, but, of course, we know that merely means the phantom menace has been vanquished, and that things will go downhill later on.
Next: The real radicalism of Marius, accidental and intentional.
*So-called because the census inventoried property as well as persons. If there was no property to inventory, the census simply counted head. The Head Count were also referred to as the proletariat, not in the modern, Marxist sense of urban working class, but something closer to what Marx would call the lumpenproletariat -- the unemployed urban rabble. Proletariat to the Romans meant one good only for producing offspring. This group might neutrally be called the propertyless. In more pejorative terms, they could be called the rabble or the mob.
**True, they did get a share of spoils from the war. But people getting a lump sum and no long-term source of income tend to burn through it fast and end up worse off than ever.
***And, having peeked ahead, McCullough ends up having Octavian keep Marius' system of enlisting the Head Count as soldiers and starts giving them a routine reward after 20 years' service, but not in land, which cannot be guaranteed available, but in a pension. I do not know the historical accuracy here.