The Adventurer (Original title Mikael Karvajalka) by Mika Waltari is a fictional tale of young Finnish man, Mikael Karvajalka, set in 16th century medieval Europe. The main character Mikael is shown as an intellectual but rather naive person, starting his life as an orphan bastard who pursues for a better social status with help of friendly people and by means of theological studies, but ends up drifting along the historical events throughout Europe rather than being able to steer his life himself.
The book begins in the city of Turku and follows Mikael along an adventure througout Europe. The book depicts many actual historical events with a rich style, although Mikael's involvement in the events is ficticious. The historical events featured in the book include::
- Conquest of Sweden, Stockholm bloodbath and eventually downfall of king Christian II of Denmark.
- Protestant reformation and related peasants' war in Germany, Luther and Müntzer themselves appearing as side characters.
- Spanish monarch sending conquistadors to New World, Mikael almost made to join Pizarro's expedition.
- Wars in 16th century Europe and expansion of Ottoman empire.
- Plundering of Rome (Sacco di Roma) during reign of Pope Clement VII
The first half of the book is of Mikael Karvajalka's tale and the second half is The Wanderer (original title Mikael Hakim), by the same author.