Well, checking for the crime rate between different races and attributing it to "race", instead of looking for the underlying causes, is the epitome of racism.
No different from 18th-19th century scholars, who concluded that blacks had inferior intelligence and reasoning skills etc, which they might indeed have as individual examples under study -- but those scholars also forgot to account for the fact that blacks didn't have the schooling and freedom to develop their personality, or that their original culture was stolen from them and they were abducted and had to operate in a hostile and foreign environment.
>As far as medieval history and the other things you've mentioned go, every type of tribe on this planet has engaged in conquest and warfare. Some won. Some lost.
And some caused endless bloodshed and massacre all over the world for profit and control, and those tended to be whites, from them, to the modern world and wars for oil and strategic interests...