Secrets of the Dead - Catastrophe! (VHS, 2000)

This is an episode of a PBS series, and it's an absolute must-see. If you have even the slightest interest in history at all, any questions as to why exactly the Dark Ages were so bad and why we lost so much after the fall of Rome, And if you have any doubts about what climate change can do to human civilzation, get a copy of this and pay attention. The answers are here. This is well worth your time and money. I recommend it highly! There is a book also, Catastrophe by David Keys, that goes into much more detail-look for it, too!