Where can I find out if an epidemic happened at a particular time in history in a particular place? In Berks County Pennsylvania, there seem to be a rash of infant deaths in my Butz/Butts family in the 18th century. I found one identified as smallpox. I know there were smallpox epidemics sweeping the states around the time of the Revolutionary War, but don't know if there is a good source for records of such epidemics.