Alaric died suddenly after a short fever. He was somewhere around forty years old. For all his urbane sophistication and his desire to become a Roman, he was given a truly barbarian funeral. The course of the river Busento was diverted and his body buried under its bed. Then the river was restored to its normal course and the captives who had worked on it were killed. The location of his body has remained a secret ever since. The secret of what exactly he was doing in southern Italy has remained just as obscure. Gibbon assumes that his interest in Sicily was as a stepping stone to Africa. Africa fed Rome, so if he wanted to control one he had to control the other. Maybe this marks his ambition to become in effect the ruler of the Roman world. Or maybe his reasoning was that Africa represented a defendable home for his people with the resources that they needed.
Whatever he had in mind for the future, what he had already done was noteworthy enough. His attack on Italy had wrecked the Western Empire. Before Alaric the Rhine frontier was still maintained, and the Danube frontier could conceivably have been re-established. Without Alaric as an adversary Stilicho might well have founded a new dynasty that could have put the empire on a sound footing. But Stilicho himself was the victim of the destabilisation brought about by Alaric.
The attack on Rome was a blow to the prestige of the empire which changed the situation in the west forever. The stunning nature of this news is apparent in the writing of St Augustine of Hippo. He ended up in Hippo as a result of the activities of Alaric. He was in fact one of the diaspora of dispossessed Romans around the empire for whom the sack of Rome represented a personal disaster. We still have the saying ‘All roads lead to Rome’. The roads might still lead there but the economic flows that made Rome a cog around which the wheels of the empire rotated were severely disrupted. Some forever. Rome had been losing its pre-eminent position for a long time in the empire it had founded, but it never had such a jolt as this one. And it never recovered.
Large swathes of Italy were wrecked. Italy had been the beneficiary of the wealth of the empire combined with centuries of more or less uninterrupted peace. It was plum sacking territory and the Goths took full advantage of it.
The sack of Rome profoundly affected the development of Christianity. Up until then it had been a top down religion whose growth had been achieved by coercion. When Honorius had brought in a law forbidding forced conversions three bishops from Carthage had turned up to argue against it. The fall of Rome showed the weakness of this approach. The man who took this on the chin was Saint Augustine. Augustine had started his career working with the formidable Ambrose of Milan. To me, he very much represents the kind of Roman who in previous eras would have been an effective administrator and would have made some kind of contribution to the development the empire. Now, like many others, he devoted himself to partisan theological disputes. But he saw a bit deeper and thought a bit harder than average.
The collapse of Roman power must have come as a profound shock to him. And it showed the weakness of the party he had signed up for. Without a powerful patron Christianity was extremely vulnerable. In the long run it needed to not only win over elites, it needed to hold its own in intellectual debates with other faiths. In particular, we see him sparring with the pagans who not only had a much more coherent philosophy but they also had a long tradition to draw on. And on top of that, the sack of Rome was not exactly a good advert for the efficacy of the Christians’ god.
In his City of God Augustine takes on the argument that the Christian god had let his followers down by allowing Rome to be sacked by its enemies. The reasoning isn’t exactly watertight, but it does the job. Augustine goes on to lay out a much more coherent framework for Christianity than it had had up until then. It wouldn’t really be accurate to call Augustine a great philosopher, or even that great a theologian. But the work he did filled a hole and gave Christianity enough intellectual weight to win people over on its own merits rather than through its political benefits. He ransacks a lot of neoplatonic ideas and presses them into service. This is done so well that it became possible to think of neoplatonism as something that was almost compatible with Christianity. It wasn’t inevitable that Christianity would survive the empire that had spread it so far. But Augustine’s work made it much more likely.