It is actually categorized by 'manner...or circumstances' of death... family, lovers, battles..nautical. etc....even death attempted but thwarted.
One can simply browse the index/indices by ballad #, listing the number of deaths in various sources..(Child, Bronson, the Digital Tradition)

Obviously, one could spend a lifetime filling several volumes with detailed analysis of the purported 'historical' and cultural events... but this is a great summary of the theme.