The Celtic phenomenon of the "blood feud" demanded "an eye for an eye," and usually descended into murder. Disagreements between clans might last for generations in Scotland and Ireland. Due to the Celtic heritage of many whites living in Appalachia, a series of prolonged violent engagements in late- nineteenth-century Kentucky and West Virginia were referred to commonly as feuds, a tendency that was partly due to the nineteenth-century popularity of William Shakespeare and Sir Walter Scott, authors who both wrote semihistorical accounts of blood feuds. These incidents, the most famous of which was the Hatfield-McCoy feud, were regularly featured in the newspapers of the eastern U.S. between the 1880s and the early twentieth century. Although they were interpreted as such at the time, there is little reason to believe that these American incidents had any correlation to "feuding" in Europe centuries earlier.