For classical antiquity the division between history and poetry is often arbitrary and misleading. The history-writing of antiquity not only subsumes what we would call political science, sociology, and psychology, but is also linked to epic poetry and to moral speculation on the good life and the good community. Just as Herodotus is not fully intelligible without Homer nor Thucydides without the tragedians, so not only Livy, but also Tacitus cannot fully be understood without reference to Virgil.
Like Gorgias or Apuleius, Tacitus also reminds us that the division between poetry and prose is more fluid in ancient than in modern literature. Scholars have long recognized Tacitus' debt to Virgil, especially in vocabulary and expression. Yet there is another, more elusive quality in Tacitus which is ultimately traceable to the influence of the great epic poet. This is the creation of an atmosphere around events which confers on them a weight, penetration, and richness of suggestion which the bare facts could not possibly convey.