It is a fictional tale of a young Finnish man, Mikael Karvajalka (Hairy-foot), set in 16th century Europe.

Beginning life as an orphan bastard, he pursues a better social position with help of friendly people and by means of theological studies, but ends up drifting along through historical events across Europe rather than being able to steer his life himself.

The book begins in the city of Turku and follows Mikael along an adventure throughout Europe and the Mediterranean.

The historical events and milieu featured in the book include: The story is continued in The Wanderer, where the protagonist explores the Ottoman Empire.

[1] The Adventurer inspired Jean Auel to start her career as a writer: "It was this story that began to crystallize for me an understanding of the real power of fiction: its ability to make the reader feel.