Were the persecutions of the Jews in Medieval Europe a result of lousy weather?
Three economists — one from the University of Michigan and two from George Mason University– studied 785 expulsions of Jews from 933 European cities between 1100 and 1800 c.e. They compared these with the frequency of colder growing seasons, and the “negative income shocks” that resulted.
Their conclusion? When the weather caused the local agrarian economy to sour, there was, until the 17th century, a statistically significant rise in the expulsion of Jews.
“Viewed through this lens,” Robert Warren Anderson, Noel D. Johnson, and Mark Koyama write in a working paper for the Social Science Research Network, “our results suggest that temperature shocks put pressure on rulers to expel Jews both as a means to make up lost tax revenue as well as to quell popular violence.”
Or as a friend wrote on Facebook: “At last — some good news about global warming.”