Norwegian retroflexion exhibits some phonetic properties that do not seem to ‘make sense’. In Standard East Norwegian, an alveolar /ɾ/ causes a following alveolar coronal to become postalveolar, and in the Frogner and Arendal dialects of Norwegian, the same postalveolarisation process is triggered by a uvular /ʁ/. Comparative analyses of Norwegian dialects reveal that these properties are the results of historical changes and phonological diffusion across dialects. Theories attempting to analyse Norwegian retroflexion as phonetically ‘natural’ can neither fully account for these properties of Norwegian retroflexion nor capture the typological generalisations found across Norwegian dialects.