After the Jewish War Josephus was taken to Rome by Titus and then enjoyed the favour of Vespasian (Vit. 422–3). The first task set him was to write a history of it in Aramaic for the ‘upper barbarians’, by which he means Parthians, Babylonians, Jews beyond Euphrates and Adiabenians (B.J. I 3, 6). For his work he doubtless had access to the ‘commentarii’ of the emperor. This task may not have taken him long, but the translation into Greek (B.J. I 3) which we possess took longer, and was finished before the emperor's death, but after the dedication of the Forum Pacis (B.J. VII 158). In its leisurely composition he tells us later (c. Ap. I 50) that he had ‘certain assistants’ in the Greek language. As the work is quite uniform and smooth in style, we can only assume that J. turned his Aramaic into Greek himself to start with, and then placed the MS in the hands of assistants who systematically revised it, rewriting where necessary. No other hypothesis is possible; for no assistant could have been found sufficiently familiar with both Aramaic and literary Greek—at least it is highly improbable—and we have no reason to disbelieve J. when he says he translated his original treatise.