The Worcester Chronica chronicarum (‘Chronicle of chronicles’) is a very important and ambitious text of the first half of the twelfth century. It purports to be a history from the origins of mankind down to the year 1140, where the principal manuscript copy—Oxford, Corpus Christi College MS 157, known by the siglum ‘C’—now ends. TCD MS 502, cited by its siglum ‘H’ and now available digitally online for the first time, is one of 5 further copies of the Chronica chronicarum that descend either directly or indirectly from C (the copy preserved in the Almonry Museum in Evesham, known as ‘E’, is only a single leaf in its current form). H is thought to have been copied in the mid-twelfth century by a single scribe who may have been working at Coventry and whose last entry is for the year 1131. Annals for the period 1132-8 were added later and there are also entries written in hands that have been dated to the early thirteenth century and beyond. H formed the basis of an edition of the Chronica chronicarum composed in 1592 by the antiquary William Howard (whose mark of ownership can be found inscribed on fol. 1r in H, and also at the front of TCD MS 503, which contains a copy of John of Worcester’s Chronicula). The hand of Archbishop James Ussher has been identified as adding marginal notes in H, including against the record of the death of Florence of Worcester under the annal for 1118 on fol. 253v. As noted below, these 5 further copies descending from C are of vital importance for reconstructing the stages in which the Chronica chronicarum was composed.