Flavius Josephus writes extensively about violence - with many examples of why and what leads to violence, particularly way back when and further back in history.
About righteous, or not, causes. About good and bad men; some later becoming the opposite - given time. About people who struggled to maintain peace; and about people who desired power and did not quit until put to the sword, hanged, parted, butchered, etc.
So a skull, cleaved, may be explained by what was written.