The cross, a Roman judicial instrument for the execution of the lowest class of criminals, was adopted and adapted by Christ's followers into a potent symbol of salvation as well as a constant reminder of the historical Jesus and inspiration for daily action and devotion. The Gospel of Matthew, for example, reports Christ's injunction to take up his cross, and Paul's epistles emphasise the cross as the instrument of Christ's passion and symbol of the resurrection. Discussions of the imagery of the cross in early medieval art, by Leslie Brubaker among others, have also highlighted the representations of the cross as a tree of life and the association of the cross with imperial victory. Byzantine processional crosses and specific forms of gold and jewelled crosses with stepped bases were represented in manuscript illuminations. The latter are understood to refer to the cross that Constantine was believed to have erected after his victory at the Milvian Bridge. Beatrice Kitzinger takes images of the cross embodying this complex tradition, simultaneously evoking past, present and future, both physical and spiritual, as a means through which to explore the power of pictorial representation in the Carolingian period, especially in Carolingian manuscripts. Her discussion needs to be read within the context of the Carolingian debates about the role of images and graphic signs in relation to the practice of religious faith and theological ideas, elucidated in particular by Celia Chazelle, The crucified god in the Carolingian era: theology and art of Christ’s passion (Cambridge 2001), Thomas F. X. Noble, Images, iconoclasm and the Carolingians (Philadelphia, Pa 2009) and Ildar Garipzanov, Graphic signs of authority in late antiquity and the early Middle Ages, 300–900 (Turnhout 2018). Kitzinger's study complements this work in its emphasis on what she terms the cross's ‘present register’ and the ‘immanent nature of the sign’ in her focus on the pictorial representation of the physical cross on the pages in a selection of Carolingian Gospel books, psalters and sacramentaries. She discusses the potential of the cross ‘as concept and material form’, how it may relate to what she describes as ‘the participation in the material sensory world of the Church’, and how representations of the cross might function as an invocation of all that it could represent in its ‘fusion of theological, narrative and liturgical aspects to the reader or viewer’. Thus an understanding of the cross's historical role and the physical wooden object it was originally embraces its transformation into a sign and symbol, and the great diversity of its representation and textual contexts in manuscript decoration.

A disconcerting aspect of Kitzinger's discussion is how few of her examples are placed in any immediate historical, geographical, institutional or physical context, and how rarely she addresses the (mostly liturgical) function of the books, who might have seen these images, or the implications of the great variety in their physical size. Her claim for special developments in the Carolingian heartlands of the ninth century is further undermined by the chronological and geographical range of iconographical comparanda she includes, and by her selections among the images in the examples that she discusses in detail. The analysis of the images for the twenty-eight acrostic poems (carmina figurata) with commentary commonly known as the De laudibus sanctae crucis by Hraban Maur, for example, is sensitive to the text of Hraban's poems but oddly omits to comment on the highlighted letters in all the cross shapes in the carmina figurata. These are to be read as an extra set of statements in all the word grids of this extraordinary composition. Kitzinger also does not comment on the cross staff held by the Emperor Louis the Pious in many manuscript copies of this work. Here the cross is presented as the vexilla regis, and the king as the soldier of Christ. The letters singled out form the phrase ‘In cruce Criste tua victoria vera salusque omnia rite regis’ (‘On the cross Christ your victory and true salvation, you rule all things properly’) (see Elizabeth Sears, ‘Louis the Pious as Miles Christi: the dedicatory image in Hrabanus Maurus's De laudibus sanctae crucis’, in P. Godman and R. Collins [eds], Charlemagne's heir: new persperctives on the reign of Louis the Pious, Oxford 1986, 605–29).

A number of aspects of the presentation in this book present obstacles for the reader. The first is the repetitive and wordy style. Of Hraban Maur's set of acrostic poems already mentioned, for example, Kitzinger writes that ‘Hrabanus's work greatly helps to clarify the category of cross images whose explicit invocation of materiality is coupled with indices of utility.' I take this to mean that the pictures of a cross and the text of Hraban's poem and commentary remind viewers and readers of the original wooden cross on which Christ was crucified. All the notes, moreover, are printed at the end of the book (pp. 204–83), in a two-column format in small print. The notes themselves, more or less without exception, are lengthy and discursive, containing essential explanatory as well as tangential material in addition to the references. It is difficult to read these notes in conjunction with the main text; it becomes even more cumbersome in the e-version of the book. The bibliographical references in the notes, however, are not included in the bibliography; the latter lists ‘additional key sources for the study’ not cited in the notes. Another problem is the illustration. It is wonderful to have so many figures in colour, the actual quality and resolution is mostly very good, and the author is meticulous about providing the dimensions of her artworks the first time they are illustrated. Nevertheless, the relative scale of the examples needs to be registered when a book like the Lorsch Gospels (37 x 21.7 cm) is reproduced in little more than postage-stamp format. And the ambo from Romainmoutier (122.5 x 80 cm) is reproduced in exactly the same size of figure as the page opposite from the Rule of Benedict in Clm 19408 (17 × 10 cm).

This is certainly an exposition full of astute and subtle nuances of observation, with detailed commentary on the remarkable variety of representations of the cross in an interesting selection of Carolingian books. The discussions of the imagery in the Gellone Sacramentary (BnF, Paris, ms lat. 12048) from Meaux and the late Carolingian ‘Angers Gospels’ (Bibliothèque Municipale, Angers, ms 24) from Brittany are particularly enlightening. Kitzinger's overall claim is that such images of the physical object and all it stood for were formative in shaping the understanding of art and its function and status beyond the merely decorative, or in her words ‘used as a sign of the immanence, utility and materiality of other works of art’, but this aspect of her argument remains a possibility rather than being established.