A skull found near Venice, Italy, seems to date back to the 16th century. The skull was originally found in a mass grave of plague victims. The jaw was forcibly opened with a brick, which was a common method of preventing vampirism. This particular article points out that the woman may have been accused of witchcraft at one time, causing those who buried her to take the extra precaution.
The article goes on to talk about the European witch hunts, and explain a few old superstitions, and show a facial reconstruction done on the skull.