The graves were discovered during an archeological examination ahead of the building of a new parish house beside the Lännäs cemetery, writes the Nerikes Allehanda newspaper.
Several artifacts were recovered from the graves, including bronze and iron objects, as well as a unique set of glass beads.
“The beads are so specialized that we're assuming the graves are from the 11th century,” said archeologist Martin Edlund to the paper.
In three of the graves, skeletal remains were also uncovered, including a well-preserved cranium of a woman.
The skull section is set to be examined further using carbon-14 dating methods.