When Did Ass Become (Semi-)Proper?

 An article in the Harvard Magazine described the Harvard Law experience of a woman who preceded RBG (Orin Kerr linked to it in a tweet).  The author describes a class where women were grilled over past legal cases with language which would be embarassing.  Hers was a case involving a farmer's ass (donkey) who got out onto the road.  This happened in 1956, a year I remember well enough to know that "ass" was never mentioned in polite society; neither was "butt" for that matter, except in the context of cigarettes.  

I've been struck by changes in language usage over the years--"ass" being one.  These days it seems pretty common in the print media, much more so in entertainment.  So I decided to do an ngram search. In America its frequency of usage seems to take off in the mid '90's, reaching a peak in 2014 and declining slightly since.  (The British usage pattern differs.)

How Big Is Denmark?

This bit quoted in Marginal Revolution struck me funny, regarding the need for subtitles in Danish movies to be played in movie theaters in Denmark?

Pedersen blames the necessity for subtitles on the evolution of the use of Danish in movies. Whereas in the past, actors were focused on articulating themselves in a way understandable for everyone, their main emphasis has now shifted to being as authentic as possible. Hence, many actors have chosen not to imitate more common dialects and have stuck to local versions of Danish. “It’s a small country, but there are big differences between the Danish dialects,” Pedersen explained.

A check of wikipedia shows Denmark to have 5.8 million inhabitants, about size of Wisconsin, but Wisconsin is about 6 times bigger. Where Wisconsin has lakes, Denmark has islands, 443 of them, some 74 of which are inhabited.  That likely explains some of divergences in the Danish language.