You might find Prof. Joseph Tainter's assessment of Rome interesting. he has a very different view of what caused the Roman collapse.
In his view, the problem was that Rome based their economy on conquest and pillage. As they'd conquer places, theyd bring back gold into their economy and this would allow them to lower or eliminate taxes. During this time of expansion they did well, and the complexity of their culture increased quite a bit, but in the end, this phase had to come to an end, and Rome was unable to sustain their economy internally. Their attempts to do so involved additional complexity and a great deal of additional attempts to regulate their way out including quantitative easing of their currency.
In the end, the problems were too great and the society collapsed from within, through the very process by which they expanded (greater and greater complexity of society).
One interesting thing I would add that Herwig Wolfram suggests is that the Western Empire was particularly poorly suited because of the concentration of wealth into fewer and fewer hands, which limited the tax base and made taxes harder to collect.
The Byzantine Empire listed much longer but a couple hundred years after the Roman Empire fell, they too experienced a massive simplification when faced with the Arab invasions. They did so in a more controlled way however and survived but in doing so, Tainter suggests, transitioned from a Roman society to a medieval one.
In his view, the problem was that Rome based their economy on conquest and pillage. As they'd conquer places, theyd bring back gold into their economy and this would allow them to lower or eliminate taxes. During this time of expansion they did well, and the complexity of their culture increased quite a bit, but in the end, this phase had to come to an end, and Rome was unable to sustain their economy internally. Their attempts to do so involved additional complexity and a great deal of additional attempts to regulate their way out including quantitative easing of their currency.
In the end, the problems were too great and the society collapsed from within, through the very process by which they expanded (greater and greater complexity of society).
One interesting thing I would add that Herwig Wolfram suggests is that the Western Empire was particularly poorly suited because of the concentration of wealth into fewer and fewer hands, which limited the tax base and made taxes harder to collect.
The Byzantine Empire listed much longer but a couple hundred years after the Roman Empire fell, they too experienced a massive simplification when faced with the Arab invasions. They did so in a more controlled way however and survived but in doing so, Tainter suggests, transitioned from a Roman society to a medieval one.