Still Gathering Data

1990 forward is still unfinished; 1870s and 1880s are mostly unfinished.  But you might be interested in some of the data so far.  Total mass murder incidents: 271; dead (not including suicides)  2227; unknown weapon used 81; non-firearms: 416; firearms: 190. 

Note that these are incidents in which at least one weapon of this type was used.  It was often difficult to accurately count dead by weapon; if you beat someone's head in with an ax, then cut the throat, which caused the death? 

Many are scalpings; sometimes done on the dead but ocassionally on the living and even the conscious (one horrifying victim described the sound of his scalp being pulled off).  (Do you now understand the ferocity of white views of Indians in the 19th century?)    In many cases, the news stories do not even identify the weapon.