As the first paragraph makes clear, Vitoria wrote this relection as the continuation of On the American Indians. The colophon of the scribe Juan de Heredia states that it was delivered a few months later, on the last day of the summer term, 19 June 1539. An interesting and possibly authentic variant reading in the first paragraph of L states that the relection was read in the schools ‘at the same time as another relection’ (see footnote 2 below). This detail seems too circumstantial for Boyer to have invented; if genuine, it provides a concrete reason, lacking from the anodyne version of the passage preserved in PS, for the relative brevity of On the Law of War.

As usual, P is the basis of this version; a selection of the numerous additions and changes in LS (many of which, to judge by the one recorded in footnote 28, were made after Vitoria's death) have been noted. The recent critical edition in the Corpus Hispanorum de Pace series (Vitoria 1981) provides full details of variants in these and other witnesses (notably V), as well as exceptionally full notes on sources, which are supplemented by Barbier's excellent doctrinal commentary in Vitoria 1966.

The division of the relection into two parts, of one and two questions respectively, follows Vitoria's own indications, in the divisio at the end of the Introduction and the paragraphs at the end of 4. 1 and 5. 5 respectively.