Volume IX of the second edition of The Cambridge Ancient History has for its main theme the process commonly known as the 'Fall of the Roman Republic'. Chapters 1-12 supply a narrative of the period from 133 BC to the death of Cicero in 43 BC, with a prelude analysing the situation and problems of the Republic from the turning-point year 146 BC. Chapters 13-19 offer analysis of aspects of Roman society, institutions, and ideas during the period. The chapters treat public and private law, the beginnings of imperial administration, the economy of Rome and Italy, and the growth of the city of Rome, and finally intellectual life and religion. The portrait is of a society not in decay or decline but, rather, outstripping its strength and attracting the administrations of men who rescued it at the price of transforming it politically.

"The new CAH IX is a welcome achievement, a readable and reliable political narrative with significant thematic contributions that mark major progress in sophistication and incisiveness of thought." The Classical Journal