Immigration to Europe has a long history, but increased substantially in the later 20th century. Especially Western European countries saw a high growth in immigration after World War II and many European nations today (particularly those of the EU-15) have sizeable immigrant populations, both of European and non-European origin. In contemporary globalization, migrations to Europe have accelerated in speed and scale. Over the last decades, there has been an increase in negative attitudes towards immigration, and many studies have emphasized marked differences in the strength of antiimmigrant attitudes among European countries.