Nicola Gatta, the mayor of Candela in southeastern Italy (population 2,700), is desperate to reverse two decades of population decline and literally keep his town on the map. If you accept his invitation to move there, he will pay you about $2,300.

It’s probably no coincidence that mayors in small Italian towns are making such offers at about the same time as a populist coalition is on the verge of taking over Italy’s government.

The last time that populism — what we broadly define as political movements that ostensibly set the interests of “ordinary people” against elites as well as an “other” — swept across Europe and the United States was marked by the same combination of slow economic and fertility growth that today prevails in advanced industrialized countries in the West and Asia.

Economies have recently picked up some steam, but not before nearly a decade of sluggish economic growth — and, in most of the world, declining fertility rates. The United States is no exception: The fertility rate among Americans has hit a 30-year low.