Abstract
Under the collective threat of war, the 2022 Russian invasion would be expected to unify Ukrainians across distinct ethnic, linguistic, geographic and generational identities. Here, we show this using survey data collected in Belarus and Ukraine before and after the full-fledged invasion of Ukraine by Russia. Using our data collection waves from spring and summer of 2022, we observed attitudinal changes rarely documented before and after such an event. Our data include both the invaded country, Ukraine, as the 'treatment' and a non-invaded country, Belarus, as the 'control'. We find that, in Ukraine but not in Belarus, geopolitical views were sharply unified by the experience of the invasion, outweighing the heterogeneous group identities before the event. Our observations serve as evidence that identity fusion under collective threat can override long-standing social divisions.