We compile large datasets from Norwegian and US historical censuses to study return migration during the Age of Mass Migration (1850-1913). Return migrants were somewhat negatively selected from the migrant pool: Norwegian immigrants who returned to Norway held slightly lower-paid occupations...

In the past decade, nearly 20 studies have found a strong, persistent pattern in surveys and behavioral experiments from over 40 countries: individual exposure to war violence tends to increase social cooperation at the local level, including community participation and prosocial behavior. Thus...