How are founders’ social identities affected by societal trigger events? To address this question, we build on social identity literature and theorize how the abrupt and significant increase in the number of refugees in Europe in 2015 is related to the strength of Darwinian, Communitarian, and Missionary social identities of founders residing in the affected countries. Furthermore, we introduce a country’s percentage of foreigners before the 2015 refugee event as relevant contingency factor. Using a dataset of 6,841 nascent entrepreneurs from 24 European countries, we reveal a positive relationship between the 2015 refugee event and the strength of founders’ Communitarian identity. This relationship is even stronger when the previous percen...