She was a Danish princess, a titular queen, a Russian princess and some even say she was the Duchess of Normandy by marriage. It was his mother Estrid’s connections that granted Sven Estridsen the throne of Denmark.

Upon their deaths the bodies of both the mother and son were entombed in a church in Roskilde, and later moved to pillar tombs in the new cathedral. However, the authenticity of the remains in Queen Estrid’s tomb has always been questioned.

DNA analyses have now confirmed these suspicions. They show that the remains in this tomb belongs to a different Queen Estrid, likely one of Sven’s two daughter-in-laws who had the same name, and were also queens.

Queen Estrid, the mother of the last Viking King

Sweyn II Denmark
Sven II Denmark (By Orf3us , from Wikimedia Commons)

Sven Estridsen is known as the last Viking King of the Scandinavian Viking Era, which lasted from the 8th century to the 11th century.

Sven’s mother Estrid Svendsdatter was the daughter of King Sweyn I of Denmark. Cnut the Great who was King of Denmark, England and Norway was her brother.

It was his mother’s bloodline that assured Sven Estridsen (aka Sven II of Denmark) a place in the Danish line of succession. He emphasized this fact by taking the matronymic surname of Estridsen after her.

Queen Estrid
Dronning Estrid (By Orf3us , from Wikimedia Commons)

Estrid was known in Denmark as Queen Estrid (Dronning Estrid), even though she wasn’t married to a king or wasn’t a queen reagent.

During the peak of Viking Era, the Danish controlled large parts of Western Europe. But, by the time of Sven Estridsen’s reign the Nordic power over Europe had dwindled.

Danes had adopted Christianity by this time, and Estrid was a key figure involved in Christianity in Denmark. She is said to have initiated building of the church in Roskilde (near Copenhagen), where the royal Danish dynasty buried their dead.

Roskilde Cathedral in Roskilde, Denmark
Roskilde Cathedral in Roskilde, Denmark (By CucombreLibre from New York, NY, USA, via Wikimedia Commons)

Authenticity of Queen Estrid’s remains questioned

According to historical documents, Sven Estridsen and his mother, Estrid, were also entombed in this church. The church was replaced with a brick cathedral about 150 years later, and the remains were moved to the pillar tombs in the new cathedral.

Skulls of King Sven Estridsen (left) and Estrid (right) (Image from Dissing J et al. (2007) Forensic Sci Int)

Curators were fairly certain that the tomb of Sven Estridsen contained true remains of the king. However, there was speculation that the tomb identified as Queen Estrid’s actually contains the remains of a different woman.

This may be due to the fact that several other royals from the time period were also named Estrid. Two of Sven’s daughter-in-laws, who later went onto become queens, were named Estrid.

Genetic analyses of the remains

In 2007, researchers chose to perform DNA analyses on the remains of Sven and Estrid to shed light onto this identify problem.

They used mitochondrial DNA (mtDNA) that has a high copy number (hundreds of copies per cell). The rapid evolution rate of mtDNA makes it the most suitable and informative DNA type for the analysis of ancient human remains.

mtDNA regions
Regions of mtDNA amenable to DNA analysis

Also the strict maternal inheritance (passed on from mother-to-child only) makes it ideal for tracing maternal lines. In this case Sven and his mother should have identical mtDNA profiles.

Three regions of the mtDNA can be analyzed – two non-coding regions HVR1 and HVR2, and the coding region. Mitochondrial DNA profiles were generated from tooth samples extracted from each skeleton.

When the profiles were compared, there were two differences between the two skeletons. This meant that it is highly unlikely that the remains entombed next to Sven actually belong to his mother.

Anthropological evidence further supported this finding, showing that the remains belonged to a female that died at 30-40 years of age. According to historical records Sven’s mother died at 70 years of age.

The remains do not belong to the mother of the Viking King

The remains of Sven and Estrid are resting back in their pillar tombs. However, we know now that the female remains in the tomb labelled “Margrethe, alias Estrid, Queen of Denmark” do not belong to Sven’s mother.

A logical explanation is that the grave contains one of Sven’s two daughters in-law. They were also named Estrid and also became queens, hence the tomb name remains correct.

The DNA tests conducted in this study have defined the mtDNA profile of the last Viking King, Sven Estridsen. If you have taken the DNA Maternal Ancestry Test, you can compare your mtDNA against Sven Estridsen to see if you may have descended from the same maternal lineage as the last Danish King of the Viking Era.

Dissing J et al. (2007) The last Viking King: a royal maternity case solved by ancient DNA analysis. Forensic Sci Int. 166(1):21-7.