The excursus includes the texts of three personal letters: Pausanias to Xerxes(128.7), Xerxes to Pausanias (129.3), and Themistocles to Artaxerxes (137.4). Although there is still support for the belief that these letters are genuine documents, the case against their authenticity, which was, in my opinion, always convincing, has been further strengthened by the recent publications challenging the general credibility of the excursus mentioned at the beginning of this paper.Scholars rejecting the authenticity of the letters have concluded, explicitly or implicitly, that Thucydides composed them himself. When briefly discussing the question in my paper on the Pentecontaetia, I supported this conclusion. It does, however, involve an assumption which I now consider to be at least disputable. The letters are in oratio recta and apparently complete and unabridged, except that part of the third one (137.4) is omitted and its substance summarized in a parenthesis. Their presentation conveys an implicit claim that the text is that of the originals. Thucydides uses TcdLe to introduce the first two, as he does when introducing official documents reproduced verbatim (cf. 5.17.2). On the other hand, the much longer letter of Nicias to the Athenians from Sicily (7.11-15), which conforms to the principles of Thucydidean speeches, including the provision of Tr 6EOVTa, is introduced, like almost all the speeches, by rotLceL(7.10). Undeniably Thucydides was capable of composing, if he so wished, letters which created a specious impression of authenticity, including the oriental tone and phrasing of the letter from Xerxes to Pausanias. It is however, questionable whether, even at an early stage of his evelopment as a historian, he would have adopted a procedure so alien to the principles to which he is seen to have adhered elsewhere in the History. If he wrote the letters himself, they are unique in that he is to some extent misleading the reader by suggesting that he is reproducing the original texts whereas he knows that he is not. in other cases where he includes the text of a document, he has evidently been at pains to satisfy himself that it is authentic and accurate.