On 27 November, we organized the seminar “The Baltic Sea – a geopolitical history” at Engelsberg Ironwork. The seminar was moderated by Iain Martin. Thank you to Peter Haldén, editor-in-chief of our book, and thank you to Tobias Boestad, Axel Boltenberg, Hugo Bromley, Christian Bueger, Kjell Engelbrekt, Toumas Forsberg, Martin Hall, Mats Hallenberg, Jonas Kjellén, Morten Nordhagen Ottosen, Magnus Petersson, Kurt Villads Jensen and Rolf Fabricius Warming for your contributions to the seminar and the book.