Dio's work is traditionally divided into 80 books, though only a portion survives in its original form.
: His political thought often leans on Stoic principles, advocating for a "republican spirit" of cooperation between the princeps and the Senate rather than a return to a pure Republic. Structure and Survival
: Unlike many historians, Dio was a practicing politician. His work often reflects his senatorial biases, particularly his interest in the relationship between the emperor and the Senate.
: Nearly complete; these cover the critical period of 65 BCE to 12 BCE, detailing the collapse of the Republic and the rise of Augustus.
: Dio frequently critiques the shift from merit-based adoption (like Hadrian's) to hereditary succession, famously noting that the Roman Empire descended from a "kingdom of gold to one of iron and rust" following the reign of Marcus Aurelius.
: Exist mostly as sparse fragments or summaries (epitomes).
: The Internet Archive provides digitized versions of all 9 Loeb volumes for in-depth study. Cassius Dio — Epitome of Book 73
For detailed research or reading, the following resources are highly recommended: