This paper applies quantitative methods in palaeography. It develops tree-structured regression models of the palaeographical variation found in a synchronic corpus of texts written in orthographically less standardised late Middle English and establishes their accuracy. There are sixteen models, each one relating to a letter-shape known to distinguish the Gothic cursive scripts Anglicana and Secretary. The models predict the presence of the individual letter-shape from one or more of the following variables, in no particular order: (1) localisation of texts’ orthographic variation; (2) text-type; and (3) in-word position. The discussion asks why several Secretary letter-shapes cluster in documents localisable to County Durham and the area further north, given the script’s association with (a) institutions of national administration in the London-Westminster area and (b) orthographic standardisation. It concludes that the linguistics and the palaeography do not co-vary during this period in the history of the English language and suggests that it may illuminate studies of the gradient between Anglicana and Secretary to pay attention to provincial centres, not least Durham.