'The Annals of Tacitus, Volume 1' Summary

Tacitus' Histories and Annals together amounted to 30 books; although some scholars disagree about which work to assign some books to, traditionally 14 are assigned to Histories and 16 to Annals. Of the 30 books referred to by Jerome about half have survived.

Modern scholars believe that as a Roman senator, Tacitus had access to Acta Senatus—the Roman senate's records—which provided a solid basis for his work. Although Tacitus refers to part of his work as "my annals", the title of the work Annals used today was not assigned by Tacitus himself, but derives from its year-by-year structure. The name of the current manuscript seems to be "Books of History from the Death of the Divine Augustus" (Ab Excessu divi Augusti Historiarum Libri).