I first got interested in epidemiology when I saw the famous John Snow chart (in a Tufte book, I think?) which pinpointed the pump which caused the 1854 cholera outbreak in London. For some reason I'd gotten the impression that this was essentially the birth of epidemiology as a discipline, but it's actually been around a lot longer than that.
200 years before that time, John Graunt developed one of the first systems for recording and reporting human casualties from disease. His annually-published tables (some of which are available in Google Books) offer a fascinating peek into life in 17th-century London. Here's just one page, from 1632:
Some of those diseases might look unfamiliar, but this list of old disease names can help with the translation. Many have since been cured, and some are still with us. And we'll always have Grief, I guess.