In the majority of cases, the process of transmission for texts found in both rolls and codices in the twelfth and thirteenth centuries seems, logically, to have moved from roll to codex. Material recorded first on rolls that could be easily expanded through the addition of sheets of parchment might then be copied into sturdier books. Yet occasionally the process was reversed, with texts that were widely available in book form being copied into rolls. Part of the explanation for this must lie in the visual appearance of the resulting rolls, which contributed to shaping the experience of the user. Amongst these rather contrary objects are two rolls produced in Britain, probably in the 1230s or 1240s, that tackle history from the beginning of time to the Middle Ages, although neither roll survives completely intact. The rolls are now in London, British Library Cotton Roll XIV.12 and Liverpool, Walker Art Gallery MS 12017. Both are written in Latin, and the scope of their contents (usually together with the choice of language) distinguishes them from the royal genealogical rolls that became popular towards the end of the thirteenth century, as well as from mortuary, statutory and liturgical rolls. The Cotton and Liverpool rolls approach their subject in different ways, making use of different texts, but they are united in their use of a genealogy of Christ associated with Peter of Poitiers, which uses a diagram as a framework for textual content and which in both rolls is augmented with imagery. Peter of Poitiers’s work circulated in both rolls and codices and thus provides a starting point for an exploration of the associations of both formats for the representation of history. The continuations of the larger rolls, moreover, provide evidence for the function and status of rolls as records, together with attempts to of Poitiers to whom it is ascribed in some surviving manuscripts, a view that has been widely accepted, though Moore noted that some of the surviving manuscripts attribute the work to Peter Comestor. The close association of the two authors in the minds of those who copied or subsequently annotated this text suggests that their work was seen as complementary.