In this attempt I have not sought to go beyond the epoch of Diocletian. A summary glance, at the utmost, into the new government which was then created may fitly form the keystone of this narrative; to estimate it fully would require a separate narration and another frame for its setting--an independent historical work, carried out in the large spirit and with the comprehensive glance of Gibbon, but with a more accurate understanding of details. Italy and its islands have been excluded; for the account of these cannot be dissociated from that of the general government of the empire. The external history, as it is called, of the imperial period is dealt with as an integral part of the provincial administration; what we should call imperial wars were not carried on under the empire against those outside of its pale, although the conflicts called forth by the rounding off, or the defence, of the frontier sometimes assumed such proportions as to make them seem wars between two powers similar in kind, and the collapse of the Roman rule in the middle of the third century, which for some decades seemed as though it were to become its definitive end, grew out of the unhappy conduct of frontier-defence at several places simultaneously. Our narrative opens with the great work of pushing forward, and of regulating the frontier towards the north, which was partly carried out and partly failed under Augustus. At other points we bring together the events that occurred on each of the three chief arenas for frontier-defence--the Rhine, the Danube, the Euphrates. The remainder of the narrative is arranged according to provinces. Charms of detail, pictures of feeling, sketches of character, it has none to offer; it is allowable for the artist, but not for the historian, to reproduce the features of Arminius. With self-denial this book has been written; and with self-denial let it be read. CHAPTER I. THE NORTHERN FRONTIER OF ITALY. [Sidenote: Northern boundary of the empire.]