The total number of
Books would then have been probably one hundred and fifty.

The division into Books (_libri_ or _volumina_) is due to the author:
vi. 1, 1, 'quae ab condita urbe Romani gessere quinque libris
exposui.' The division into decades (_i.e._ sets of ten Books) is
first mentioned towards the end of the fifth century; it is merely a
conventional arrangement, the subject-matter falling naturally into
sets of fifteen Books, which again sometimes embrace three
sub-divisions each a half-decade, or two, a half-decade and a decade.

An epitome was known to Martial, xiv. 190,

'Pellibus exiguis artatur Livius ingens,
quem mea non totum bibliotheca capit.'

The evidence of the date of composition is as follows:

(_a_) i. 19, 3, 'Bis deinde post Numae regnum [Ianus] clausus fuit,
semel T. Manlio consule post Punicum primum perfectum bellum, iterum,
quod nostrae aetati dei dederunt ut videremus, post bellum Actiacum ab
imperatore Caesare Augusto pace terra marique parta.' Now, as the
first closing of the temple of Janus by Augustus was in B.C. 29, and
as Livy is silent as to the second closing after the Cantabrian war in
25, it follows that this passage was written B.C. 29-25. The use of
the title Augustus, conferred on Octavian in 27, puts the earliest
possible date two years later. The history therefore was not begun
before B.C. 27.

(_b_) ix. 36, 1, 'Silva erat Ciminia magis tum invia atque horrenda
quam nuper fuere Germanici saltus.' In this Niebuhr found an allusion
to the campaigns of Drusus, B.C. 12-9, and accordingly assumed that
the first decade was not published till B.C. 9. But the passage may
equally well refer to earlier campaigns, _e.g._ of Julius Caesar. Nor
can it be shown that the history of Dionysius of Halicarnassus,
published B.C. 7, was used by Livy for Books viii.-x. Book ix. must
have been written before B.C. 20, or Livy would have mentioned the
recovery of the standards from the Parthians in ix. 18, 9.

(_c_) xxviii. 12, 12, 'Hispania prima Romanis inita provinciarum, quae
quidem continentis sint, postrema omnium nostra demum aetate ductu
auspicioque Augusti Caesaris perdomita.' This was written not earlier
than B.C. 19, if it refers to Agrippa's victory over the Cantabrians.

(_d_) Book lix. mentioned the _lex de maritandis ordinibus_, and
consequently cannot have been earlier than B.C. 18.

(_e_) The books in which Pompeius figured were composed in the
lifetime of Augustus (T