The War With Catiline - Sallust
Tremendous near contemporary account of the Catiline conspiracy which was a really dramatic attempt to overthrow the republic by a gang of wretches led by a few dazzling rogues. This episode of Roman history is paid much less attention than it should be, being understandably overshadowed by later events. In significant supporting roles the work contains a young Caesar, Cato and Cicero. The event itself is probably best termed a violent insurrection, rather than a full blown civil war, but it exposes the deep rot and dysfunction which had already set in and which would, shortly, lead to the collapse of the republic. Readers can draw what parallels they will. Sallust is super biased, which is something to keep in mind, but its great. Can be read in one sitting. You can find it online here https://penelope.uchicago.edu/Thayer/e/roman/texts/sallust/bellum_catilinae*.html
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