If you can find a way to stream it, this is a great series on the rise of traditional Appalachian music from Bluegrass, through the Grand Ol Opry, to Western Swing, to Bakersfield, to Outlaw Country, to Dolly Parton and Modern Country, Garth Brooks and the rest.
8 two hour episodes; each is essential and all worthwhile.
We have seen 7 and will save the last one for tomorrow.
I did read somewhere that this will be on BBC 4 in the UK at some time in the near future, not exactly sure when. The PBS channel we get through Sky in the UK doesn’t appear to be scheduling this documentary at the moment.