Query: When did the grammarians first draw the line between third person plural pronouns for Dutch?
Context: There is one exception: the standard language prescribes that in the third person plural, hen is to be used for the direct object, and hun for the indirect object. This distinction was artificially introduced in the 17th century by grammarians, and is largely ignored in spoken language and not well understood by Dutch speakers. Consequently, the third person plural forms hun and hen are interchangeable in normal usage, with hun being more common.