Early Middle Danish texts of the Scanian dialect are characterised by a relatively stable use of case marking for expressing grammatical relations. Later 15th-century texts, however, display a general increase in the percentage of partial and full case neutralisations. Contrary to what scholars have traditionally assumed, I argue that these neutralisations cannot be caused solely by regular soundlaws and analogical reshapings on the expression level of the grammatical signs. Rather, the relatively predictable constituent order in the Middle Danish noun phrase made case marking redundant, causing the case system to undergo a regrammation where the original, morphologically and syntactically based paradigm developed into a purely syntactic one. More precisely, the indexical sign relations changed so that the expression of morphological case no longer indicated the mutual connection between the NP head and modifier; this relation was now indicated only by the order of head and modifier (and by number and gender agreement).