I came back to re-read these books after several decades, having seen Derek Jacobi's wonderful BBC adaptations, and then read Colleen McCullough's Masters of Rome series of novels.  The latter chronicles the demise of the Roman Republic with the ascension of Augustus after  the defeat of Marc Antony.  Graves begins his stories from about that point, but his style is focuses more on the gossip and internal intrigues, rather than the broader political struggles that McCullough portrays.  His easy style is still highly readable, but it's interesting to note anachronisms that now jump from the pages -- the military descriptions have been translated to modern concepts, with 'colonels' and 'generals' commanding 'regiments', and the German warriors fighting with 'assegais' [curiously, modern readers are more likely to be familiar with Roman terminologies, than those of the late Victorian British Empire].  But none of this detracts from Graves ability to weave a tangled tale, and he's still the one against whom later authors must be measured.