The Codex of Justinian is, together with the Digest, the core of the great Byzantine compilation of Roman law called the Corpus Iuris Civilis. The Codex compiles legal proclamations issued by Roman emperors from the second to the sixth centuries CE. Its influence on subsequent legal development in the medieval and early modern world has been almost incalculable. But the Codex has not, until now, been credibly translated into English. This translation, with a facing Latin and Greek text (from Paul Krüger's ninth edition of the Codex), is based on one made by Justice Fred H. Blume in the 1920s, but left unpublished for almost a century. It is accompanied by introductions explaining the background of the translation, a bibliography and glossary, and notes that help in understanding the text. Anyone with an interest in the Codex, whether an interested novice or a professional historian, will find ample assistance here.