The painting illustrates a passage from the Kalevala, the Finnish national epic compiled by Elias Lönnrot in the 19th century.

The scene portrayed is taken from the 43rd song of the epic, where the hero Väinämöinen, seen wielding a sword, has stolen the precious artifact Sampo from the evil witch Louhi, and she, having taken the form of a giant bird, is trying to reclaim it.

In the painting, Väinämöinen's long, flowing white hair and beard are dramatically contrasted by his strong, muscular body.

According to Gallen-Kallela's notes, however, the deal was amicably dissolved when the patron's wife had an extremely negative reaction to the finished work.

Afterwards, The Defense of the Sampo was purchased by the Turku Arts Association (Turun taideyhdistys) for the previously unheard-of price of 4000 marks.