Opening the floodgates? European migration under restrictive and liberal border regimes 1950-2010

The effect of ‘open borders’ on migration has been the subject of substantial controversy. Political rhetoric and media images help stoke fear of uncontrolled mass migration that in turn fuels arguments in favour of tighter immigration regulations and border controls to ‘bring migration back under control’. In public debates, removing migration barriers is frequently portrayed as tantamount to ‘opening the floodgates’. However, immigration liberalisation may increase also circulation and return, rendering the effect on net migration theoretically ambiguous. Drawing on bilateral flow data over the 1959-2010 period contained in the DEMIG C2C database, this paper uses European Union (EU) enlargement as a case study to assess how liberalising border regimes affected migration flows. The analysis suggests that, with some exceptions, liberalisation boosted circulation rather than led to a structural increase in intra-EU migration. While removing migration barriers can lead to migration surges—particularly when economic gaps between origin and destination countries are large—these tend to be temporary, after which migration becomes more circular and tends to consolidate at lower levels. And while intra-regional circulation in the EU has grown, closing external EU borders has increasingly pushed non-EU migrants into permanent settlement along with significant family migration. These factors help to explain the structural rise in non-EU immigration, defying policy expectations that opening internal borders would decrease non-EU immigration.