The opera by Strauss (the waltz guy) and was written about the time Grant was president and we were about to celebrate our first hundred years as a nation. It has nothing to do with either - just placing it in time for you. The synopsis is crazy and the Wiki posting of it (here) is spot on.
We have, for a century now, mainly gone to movies for our "nights out" entertainment. 130 years ago people went to see this type of thing. A hundred years from now people will look at our Hollywood plot lines with the same "ha ha ha" that we look back at the Bat.