The atmosphere of Dio's Roman History is serious to a degree. Its author never loses sight of the fact that by his labor he is conferring a substantial benefit upon mankind, and he follows, moreover, a particular historical theory, popular at the time, which allows little chance for sportiveness or wit. Just as the early French drama could concern itself only with personages of noble or royal rank, so Dio's ideal compels him for the most part to restrict himself to the large transactions of governments or rulers and to diminish the consideration that idiosyncrasies of private life or points of antiquarian interest might otherwise seem to claim. The name of this ideal is "Dignity" (ογκος is the Greek), a principle of construction which is opposed to a narration adorned with details. However much it may have been overworked at times, its influence was certainly healthful, for it demanded that the material be handled in organic masses to prevent the reader from being lost in a confused mass of minutiæ. Racy gossip and old wives' tales are to be replaced by philosophic reflection and pictures of temperament. Instead of mere lists of anecdotes there must be a careful survey of political relations. Names, numbers, and exact dates may often be dispensed with. Still, amid all this, there is enough humor of situation in the gigantic tale and enough latitude of speech on the part of the acting personages to prevent monotony and to render intellectual scintillations of the compiler comparatively unnecessary. Occasionally, for the sake of sharper focus on the portrait of some leader, Dio will introduce this or that trivial incident and may perhaps feel called upon immediately, under the strictness of his self-imposed régime, to apologize or justify himself.
The style of the original is rendered somewhat difficult by a conscious imitation of the involved sentence-unit found in Thukydides (though reminiscences of Herodotos and Demosthenes also abound) but gives an effect of solidity that is symmetrical with both the method and the man. Moreover, one may assert of it what Matthew Arnold declared could not be said regarding Homer's style, that it rises and falls with the matter it treats, so that at every climax we may be sure of finding the charm of vividness and at many intermediate points the merit of grace. It is a long course that our historian, pressed by official cares, has to cover, and he accomplishes his difficult task with creditable zeal: finally, when his Thousand Years of Rome is done, he compares himself to a warrior helped by a protecting deity from the scene of conflict. Surely it must have been one of the major battles of his energetic life to wrest from the formless void this orderly record of actions and events embroidered with discussion of the motives for those actions and the causes of such events.
Dio has apparently equipped himself extremely well for his undertaking. A fragment edited by Mai (see Fragment I) seems to make him say that he has read every available book upon the subject; and, like Thukydides, he is critical, he is eclectic, and often supports his statements by the citation or introduction of documentary testimony. His superstition is debasing and repellent, but works harm only in limited spheres, and it is counterbalanced by the fact that he had been a part of many events recounted and had held high governmental offices, enjoying a career which furnished him with standards by which to judge the likelihood of allegations regarding earlier periods of Rome,—that, in a word, he was no mere carpet-knight of History. He is honestly conscientious in his use of language, attempting to give the preference to standard phrases and words of classical Greek over corrupt idioms and expressions of a decadent tongue; it is this very conscientiousness, of course, which leads him to adopt so much elaborate syntax from bygone masters of style. Finally,—the point in which, I think, Dio has come nearest to the gloomy Athenian,—something of the matter-of-fact directness of Thukydides is perceptible in this Roman History. The operator unrolls before us the long panorama of wars and plots and bribes and murders: his pictures speak, but he himself seldom interjects a word. Sometimes the lack of comment seems almost brutal, but what need to darken the torture-chamber in the House of Hades?
There are two ways of writing history. One is to observe a strictly chronological order, describing together only such events as took place in a single year or reign; and the other, to give all in one place and in one narration the story of a single great movement, though it should cover several years and a fraction,—or, again, to sketch the condition of affairs in one province, or valley, or peninsula for so long a time as the story of such a region seems to possess unity of development. The first kind of writing takes the year or the reign as its standard, whereas the second uses the matter under discussion or some part of the earth in the same way: and they may accordingly be called, one, the chronological method, and the other, the pragmato-geographical. The difference between the two is well illustrated by the varying ways in which modern works on Greek history treat the affairs of Sicily.
The first plan is that which Dio follows, and his work would have been called by the Romans annales rather than historiæ. The method has its advantages, one of which is, or should be, that the reader knows just how far he has progressed; he can compare the relative significance of events happening at the same time in widely separated lands: he is, as it were, living in the past, and receives from week to week or month to month reports of the world's doings in all quarters. On the other hand, this plan lacks dramatic force; there are sub-climaces and one grand climax: and the interest is apt to flag through being obliged to divide itself among many districts. The same results, both good and bad, are observable in Thukydides, whom Dio follows in constructive theory as well as style. It has already been said that our historian sacrifices sharpness of dates to the Onkos, depending, doubtless, on his chronological arrangements to make good the loss. Usually it does so, but occasionally confusion arises. Whether because he noticed this or not, he begins at the opening of the fifty-first book to be accurate in his dates, generally stating the exact day. Rarely, Dio lets his interest run away with him and mixes the two economies.
If we read the pages closely, we find that by Dio's own statement his work falls properly into three parts. The first consists of the first fifty-one books, from the landing of Æneas to the establishment of the empire by Octavianus. Up to that time, Dio says (in LIII, 19), political action had been taken openly, after discussion in the senate and before the people. Everybody knew the facts, and in case any authors distorted them, the public records were open for any one to consult. After that time, however, the rulers commonly kept their acts and discussions secret; and their censored accounts, when made public, were naturally looked upon by the man in the street with doubt and suspicion. Hence, from this point, says the historian, a radical difference must inevitably be found in the character of his account.
The second portion, opening with Book Fifty-two, ends at the death of Marcus Aurelius (180 B.C.). In LXXI, 36, 4 Dio admits that the old splendor ended with Marcus and was not renewed. His history, he says, makes here a sheer descent (καταπιπτει) from the golden to the iron age. It fades, as it were, into the light of common day in a double sense: for the events succeeding this reign Dio himself was able to observe as an intelligent eyewitness.
The third section, then, extends from the beginning of Book Seventy-two to the end of the work. Here Dio breaks away oftener than before from his servility to the Dignity of History, only to display a far more contemptible servility to his imperial masters. According to his own account he stood by and passively allowed atrocities to be multiplied about him, nor does he venture to express any forceful indignation at the performance of such deeds. Had he protested, the world's knowledge of Rome's degenerate tyrants would undoubtedly have been less complete than it now is; and Dio was quite enough of an egotist to believe that his own life and work were of paramount importance. If we compare him unfavorably with Epictetus, we must remember that the latter was obscure enough to be ignored.
In both the second and the third parts, that is to say throughout the entire imperial period, Dio is conceded to have committed an error in his point of view by making the relations of the emperor to the senate the leading idea in his narrative and subordinating other events to that relation. Senator as he was, he naturally magnified its importance, and in an impartial estimate of his account one must allow for personal bias.
Our historian's sources for the earlier part of his work are not positively known. He has been credited with the use of Livy, of Cœlius, of Appian, and of Dionysios of Halicarnassos, but the traces are not definite enough to warrant any dogmatic assertion. Perhaps he knew Tacitus and perhaps Suetonius: the portrait of Tiberius is especially good and was probably obtained from an author of merit. But there were in existence a great multitude of books inferior or now forgotten besides the works of the authors above mentioned; and Dio's History in general shows no greater evidence of having been drawn from writers whom we know than from others whom we do not know.