Matt Johnson wrote:
I'm wondering if we have any additional details about the localities that adopted DST during this period and those that did not?
Yes, I have a copy of Shanks's American Atlas, which has 617 8.5x11" pages of closely spaced 3-column data that cover the period in question. Shanks has an entry for Nashville's time zone history, along with entries for thousands of other locations in Tennessee. I'm happy, to be honest, that all this stuff is out of scope for the tz database, as it'd be a lot of work to verify it. Quite possibly a lot of it is wrong, though I expect the American Atlas is more reliable than Shanks's International Atlas. The situation for Nashville was particularly tricky. See: http://mm.icann.org/pipermail/tz/2015-April/022167.html