It is not known exactly when Bede's Historia Ecclesiastica was translated into Old English. The translation was certainly complete by the early decades of the tenth century, from when the earliest extant manuscripts of the translation date. A terminus post quem is less easy, though the probability that all the extant manuscripts derive from a single exemplar written in the Mercian dialect makes it unlikely that the translation is earlier than about 800. The Mercian origin of the text makes it unlikely that the translation is by King Alfred, contrary to Ælfric's reference to Bede's historia anglorum ða ðe Ælfred cyning of ledene on Englisc awende. Nonetheless, it is possible that the translation was made at Alfred's request or was comandeered for Alfred's programme to provide the 'books most needful for men to know' (ða ðe niedebeðearfosta sien eallum monnum to wiotenne). As Whitelock's 1984 study of the chapter titles prefixed to the translations shows, the translation might have been sent from a central scriptorium to all major religious houses in England, like the Alfredian translation of the Pastoral Care.
The Old English Bede is usually described as a 'translation', though it is an abridgement in which definite principles of adaptation can be discerned. The Old English version omits most of the letters, documents and epitaphs quoted by Bede and removes material concerned exlusively with the Celtic church and the papacy. The translator was careful to omit cross references to passages he had left out, and supplied information to explain passages that became unclear due to a previous omission. Bede's careful acknowlegement of his sources is also curtailed, leaving Bede himself as the sole authority for the events recorded. Not all changes are explicable, particularly the descision to move Pope Gregory's responsa to the interrogationes of Augustine (of Canterbury) from their position towards the end of the first book to a postion between the third and fourth books.
Though there is much to be admired in the carefulness of the abridgement, the style of the translation is less satisfactory. Probably written as a crib for those unable to read Bede's elegant Latin, the translation assumes a readership of limited intellectual interests and capabilities, an audience that needs to be told (for example) that Genesis is the first book of the Pentateuch. The translation slavishly follows the syntax of the Latin (though it has been suggested that this was a characteristic of learned prose) and is often painfully verbose. Indeed, the translator's most typical stylistic affectation is to translate one Latin word with two (or three) Old English synonymns, a trick that may have its origins in interlinear glosses to Latin texts (see Kuhn 1947). Nonetheless, the translator occasionally comes up with a startling poetic phrase, for instance the rendering of Bede's paruissimo spatio ('a very short period') as 'an eagan byrhtm' ('the blink of an eye') in the famous sparrow episode (II.13).
Further Reading: Bately 1988 gives a thorough overview of early Old English prose. Whitelock 1962 is essential on the Old English Bede. Recent articles by St Jacques 1983 and Discenza 2002 are less satisfying.