As a rule, these inscriptions have only incidental importance in the way of fixing dates or establishing details as to the economic history. On the other hand, such a tablet as the Monumentum Ancyranum gives important information as to the life of Augustus, and such pictorial presentations as occur on the columns of Trajan and Marcus Aurelius are of the utmost importance in reproducing the life-history of the period. For mere matters of chronology--having also wider implications on occasion--the large series of coins and medals is of inestimable importance. Without these various inscriptions, as has been said, many details of imperial history now perfectly established must have remained insoluble. Nevertheless, after giving full credit to the inscriptions as sources of history, the fact remains that for most of the important incidents that go to make up the story, and for practically all the picturesque details of political history, the manuscripts are still our chief sources. The authors whose works have come down to us are relatively few in number, and may be briefly listed here in a few words. For the earliest imperial period we have the master historian Tacitus, the biographer Suetonius, the courtier Velleius Paterculus, and the statesman Dion Cassius. As auxiliary sources the writings of Martial, Valerius Maximus, Pliny, and the _Jewish Wars_ of Josephus are to be mentioned. For the middle period of imperial history Dion Cassius and Herodian, supplemented by Aurelius Victor and the other epitomators, and by the so-called Augustan histories or biographies, are our chief sources. After they fail us, Zosimus and Ammianus Marcellinus have the field practically to themselves, gaps in their work being supplied, as before, by the outline histories. Details as to these writers will be furnished, as usual, in our general bibliography. [Illustration] THE FIRST CENTURY OF EMPIRE: AUGUSTUS TO NERO (30 B.C.-68 A.D.)