Apart from this litigation with his guardians, we know little of Demosthenes' youth and early manhood. Various stories have come down to us (for the most part not on the best authority), of his having been inspired to aim at an orator's career by the eloquence and fame of Callistratus; of his having overcome serious physical defects by assiduous practice; of his having failed, nevertheless, owing to imperfections of delivery, in his early appearances before the people, and having been enabled to remedy these by the instruction of the celebrated actor Satyrus; and of his close study of the _History_ of Thucydides. Upon the latter point the evidence of his early style leaves no room for doubt, and the same studies may have contributed to the skill and impressiveness with which, in nearly every oration, he appeals to the events of the past, and sums up the lessons of history. Whether he came personally under the influence either of Plato, the philosopher, or of Isocrates, the greatest rhetorical teacher of his time, and a political pamphleteer of high principles but little practical insight, is much more doubtful. The two men were almost as different in temperament and aims as it was possible to be, but Demosthenes' familiarity with the published speeches of Isocrates, and with the rhetorical principles which Isocrates taught and followed, can scarcely be questioned.
In the early years of his manhood, Demosthenes undertook the composition of speeches for others who were engaged in litigation. This task required not only a very thorough knowledge of law, but the power of assuming, as it were, the character of each separate client, and writing in a tone appropriate to it; and, not less, the ability to interest and to rouse the active sympathy of juries, with whom feeling was perhaps as influential as legal justification. This part, however, of Demosthenes' career only concerns us here in so far as it was an admirable training for his later work in the larger sphere of politics, in which the same qualities of adaptability and of power both to argue cogently and to appeal to the emotions effectively were required in an even higher degree.
At the time when Demosthenes' interest in public affairs was beginning to take an active form, Athens was suffering from the recent loss of some of her most powerful allies. In the year 358 B.C. she had counted within the sphere of her influence not only the islands of Lemnos, Imbros, and Scyros (which had been guaranteed to her by the Peace of Antalcidas in 387), but also the chief cities of Euboea, the islands of Chios, Cos, Rhodes, and Samos, Mytilene in Lesbos, the towns of the Chersonese, Byzantium (a city of the greatest commercial importance), and a number of stations on the south coast of Thrace, as well as Pydna, Potidaea, Methone, and the greater part of the country bordering upon the Thermaic Gulf. But her failure to observe the terms of alliance, laid down when the new league was founded in 378, had led to a revolt, which ended in 355 or 354 in the loss to her of Chios, Cos, Rhodes, and Byzantium, and of some of the ablest of her own commanders, and left her treasury almost empty. About the same time Mytilene and Corcyra also took the opportunity to break with her. Moreover, her position in the Thermaic region was threatened first by Olynthus, at the head of the Chalcidic League, which included over thirty towns; and secondly by Philip, the newly-established King of Macedonia, who seemed likely to displace both Olynthus and Athens from their positions of commanding influence.[1]