Answer:
Because he was a conscious literary stylist, both his thought and his manner of expression gave life to his work. Greek historiography had defined ways of depicting history: one could analyze events in plain terms, set the scene with personalities, or heighten the dramatic appeal of human action. Each method had its technique, and the greater writer could combine elements from all three. The Roman “annalistic” form, after years of development, allowed this varied play of style in significant episodes. Tacitus knew the techniques and controlled them for his political interpretations; as a model he had studied the early Roman historiographer Sallust.
It is finally his masterly handling of literary Latin that impresses the reader. He wrote in the grand style, helped by the solemn and poetic usage of the Roman tradition, and he exploited the Latin qualities of strength, rhythm, and colour. His style, like his thought, avoids artificial smoothness. His writing is concise, breaking any easy balance of sentences, depending for emphasis on word order and syntactical variation and striking hard where the subject matter calls for a formidable impact. He is most pointed on the theme of Tiberius, but his technique here is only a concentrated form of the stylistic force that can be found throughout his narrative.
Tacitus’ work did not provide an easy source for summaries of early imperial history, nor (one may guess) was his political attitude popular in the ruling circles; but he was read and his text copied until in the 4th century Ammianus Marcellinus continued his work and followed his style. In modern scholarship Tacitus’ writings are studied seriously—with critical reservation—to reconstruct the early history of the Roman Empire. On the literary side they are appreciated as stylistic masterpieces.
