The unique second plural imperative ending -er (-ær) in older Danish has been previously explained by Krogh (1995) as enclisis of the plural pronoun *īʀ and of common origin to the Old Norwegian second plural ending -ir, used in all moods. The present article explains the latter as the result of proportional analogy with the dual pronoun (þ)it > (b=þ)ið whereas the enclisis hypothesis is still the best explanation for the former. Synchronically, the Dan- ish ending functions to differentiate the plural from the singular in the imperative mood.