The Genesis-based poetry of Junius 11 vastly outweighs the other poetic contents of the manuscript in the bulk of its verse and in the quantity of visual and textual embellishment that accompanies it in the extant leaves of the first eleven quires of the manuscript. Comprising 2937 lines in its present state, the copy of the Genesis sequence may have embodied more than 3350 lines before the excision of leaves from quires 2–3 and 9–11 of the manuscript. Pp. 1–142 of Junius 11 thus bear witness to the longest sequence of thematically integrated verse in the corpus of Old English, with the dubious exception of the metrical gloss of Psalms LI–CL in the Paris Psalter. The only extant Old English poem of comparable length is Beowulf, comprising 3182 lines. Other features of Junius 11, both textual and iconographic, corroborate the pre-eminent position of the Genesis-based verse in the collection. Genesis A and B are the only compositions whose text has been provided with illustrations; both of their texts have been corrected and supplied with additional points and accents by readers. The text assigned to Genesis B in particular has been revised systematically–evidently in accordance with a phonologically informed programme of orthographic normalization. In the course of the later medieval transmission of Junius 11, the Genesis-based material seems often to have served to represent the entire contents of the manuscript. Two hands, one medieval and one early modern, have added the only titles to appear in Junius 11: ‘Genesis in anglico’ and ‘Genesis in lingua Saxania’ [sic]. An early fourteenth-century Christ Church booklist entry, ‘Genesis anglice depicta’, has been seen as a possible reference to the codex as a whole.