This book has an autobiographical back-story. It addresses a topic that has intrigued me since my earliest memories. As now happens with growing frequency, I am a product of parents from different countries. I acquired American citizenship from my father and French citizenship through my mother. In my childhood, I spent more time in the United States, but I regularly enjoyed long summers in Normandy with my French grandparents, as well as the occasional sabbatical year in Paris. Growing up, I had close friends and deep roots in both places that persisted despite the absences in between, and I genuinely felt at home in both countries. This occurred despite the torrent of questions I endured – “do you prefer French or English?” “Is it better here or there?” “Are you more American or more French?” – to which I have never quite known how to respond. The real answer, which still holds today, is that my experiences in both countries have shaped my identity, and I could not be one without the other.

My own experience is far from unique. Millions of other children have been born into two citizenships, and many millions more – including my parents – have acquired a new citizenship later in life by becoming naturalized citizens of another country (though, as shown in this book, not all can keep their prior citizenship). As immigration flows intensify and as the world becomes a smaller, more fluid place, the issue of citizenship has become increasingly timely and relevant.