So, I recently learned that there's this song called 「通りゃんせ」, which I guess would be familiar to all of you who have lived in Japan.
The grammatical form "通りゃんせ" (and later in the song, "[下]{くだ}しゃんせ") is completely unfamiliar to me. The Japanese Wikipedia article for the song gives 通りなさい as a translation, which is good to know, but I would like to know more about this form. I figure that it is either archaic or at least non-標準語, judging from the use of じゃ as a copula and 通しゃせぬ as the negation of, uh, I guess 通す or some related verb.