For migrants, becoming a citizen of the host country is a complex decision. The work of Thomas Soehl, a sociology researcher at McGill University, shows the important role played by social networks in this process.

Research on this topic often presents the decision as an individual choice based on economic costs and benefits. This approach ignores the social component of the decision, particularly in the case of migrants who arrived in their host country as children or teenagers. To shed more light on the subject, Thomas Soehl conducted a quantitative analysis using American immigration data. In particular, he observed the correlation between the timing of naturalization of young migrants and that of other members of their family. Naturalizations occurring close together suggest a coordinated process.

The researcher also conducted around fifty interviews with individuals who had emigrated to the United States, to gain a better understanding of the influence of their social network. The results show that social network influence is driven by “complex contagion”. Simple contagion can be likened to catching a cold by coming into contact with a single contaminated person. Complex contagion requires close contact with multiple people.

In other words, migrants do not decide to acquire host-country citizenship simply because they have spoken to someone who has done it. They are more influenced by people very close to them or whose situation is very similar to their own. This social influence plays an even greater role when a number of people share the same message about acquiring citizenship.

Thomas Soehl’s work offers new insights into a crucial decision that concerns more and more people in today’s societies.


Thomas Soehl, Roger Waldinger & Renee Luthra (2020) Social politics: the importance of the family for naturalisation decisions of the 1.5 generation, Journal of Ethnic and Migration Studies, 46:7, 1240-1260, DOI: 10.1080/1369183X.2018.1534584