Katla is based on various historical and archaeological sources, ranging from religious chronicles and travel logs to epic sagas and runestones. We initially encounter Katla in a minor role in Saint Rimbert’s biography of Saint Ansgar, which mentions her travelling to Dorestad, a bustling trading centre on the banks of the Dutch Rhine, in 852. It was her pious mother’s final wish that Katla hand out her large inheritance to the poor in Dorestad, given there were too few on the island of Birka, where they lived. We do not know if she ever returned home.

Katla’s story is also the story of a long-murky period of European history, and to recreate the world through which she passed, Van der Tuuk explores how the Vikings lived on Birka, which was in its own right an important stop on the long trade routes that connected Sweden with Constantinople and even the Caspian Sea. It was a time in which traders and raiders could be one and the same, and Dorestad, in turn, served as an important link between western and northern Europe in the trade of enslaved people and luxury goods. Van der Tuuk also examines daily life in the towns and villages, customs surrounding magic and religion, techniques in shipbuilding and navigation, and the hazards of travelling by boat. We learn of the many power struggles between the Vikings, Frisians, Franks and peoples of the British Isles.

Van der Tuuk populates this world with the warring rulers, explorers and everyday people and does away with many cultural cliches. He also includes photos of artefacts and historic sites in the present day. Central to this short, accessible history is the free and independent position of women in medieval Scandinavian society in contrast to the rest of Europe, as well as the Nordic tradition of proud, strong women in their sagas. Katla is a perfect example.