Florian Coulmas is Senior Professor of Japanese Society and Sociolinguistics at the IN-EAST Institute of East Asian Studies, University of Duisburg-Essen. He has prevoiusly held positions at Georgetown University, the National Institute of Japanese Language and Linguistics, and Chuo University. He is the author of the OUP volumes Guardians of Language: Twenty Voices Through History (2016), An Introduction to Multilingualism (2017), Identity: A Very Short Introduction (2019), and Language, Writing, and Mobility: A Sociological Perspective (2022).