The top-line finding is that, according to the available scholarship, murder rates in Western Europe have fallen by 40- or 50-fold since the Middle Ages. In Italy, for instance, there were more than 70 homicides for every 100,000 people in the 1400s. Italy’s murder rate is closer to 1 in 100,000 today.

You see similar patterns, to varying degrees, wherever in Western Europe there’s enough data to estimate long-term trends. While estimated homicide rates in the 1300s ranged from 20 per 100,000 in England more than 50 per 100,000 in Italy, in those regions murder rates fell sharply over subsequent centuries, and converged to about 1 per 100,000 today, according to United Nations statistics.

But the United States stands as a country apart when it comes to homicide measurements. In 2014, for instance, the murder rate in the U.S. stood at 4.5 homicides for every 100,000 people. That’s roughly equivalent to the murder rate in Italy in 1912, or England’s murder rate in the 1600s.