Earlier in the year, archaeologists exhumed several bodies from a tomb in Riddarholmen Church in central Stockholm thought to contain Ladulås in order to carry out DNA tests to determine who exactly was buried along with the king.
Subsequent tests revealed, however, that all of the nine skeletons were at least 200 years too young to be Ladulås and his family, leaving researchers puzzled as to where the the king may actually be buried.
According to the scientists, however, there is no doubt about the accuracy of the tests.
”You can trust these to 100 percent. The carbon-14 method is very accurate,” said professor Göran Possnert of the Ångström Laboratory at Uppsala University to daily Svenska Dagbladet (SvD) on Friday.
Magnus Ladulås' grave had been opened on a previous occasion, in 1915, when it was concluded that his skeleton showed signs of sickness.
Researchers hoped that modern techniques would be able to establish the exact cause of death.
"We know that his wife, a grandchild and a daughter are in there. We will now find out who the others are," project-leader Maria Vretmark told Dagens Nyheter at the time of the excavation.
But it turned out that the nine people who were buried in the tomb, excavated last year, were all buried sometime between 1430 and 1520.
”Already the first of the different analyses we carried out revealed that King Johan III in the 1570s placed the Magnus Ladulås tomb over the wrong grave,” Vretmark told DN on Friday.
Vretmark thinks that the discovery is ”sensational” and a ”fantastic story”.
”It shows the need for to question sources, but also how the men of power in the 1400 and 1500s used history to further their political gain,” she said.
Four hundred years later, the historical hoax has been exposed.
However, the team continue to be convinced that the remains of Ladulås are buried in the church.
”It was stipulated in the last will and testament of Magnus Ladulås that he shall be buried in the church, he was the monastery's main benefactor. They tried to achieve a sort of sainthood for Magnus Ladulås. He was important for the monastery and it is completely unlikely that they would have tidied away his skeleton,” Vretmark told SvD.
The scientists now believe that the body is buried in the south grave in front of the sanctuary.
An application to open the grave and exhume those buried there has been dispatched to the Swedish Royal Court.
Permission had been initially granted to open Magnus Ladulås' grave in 2010. The application was submitted in connection with the planning of the 800 year celebrations for Birger Jarl">Birger Jarl in 2010.
The fabled Magnus Ladulås (Birgersson) was born in 1240 and reigned from 1275-90, succeeding his brother Valdemar, who he ousted from the throne with the help of the Danes.
Commonly known as Magnus III outside of Sweden, Magnus Ladulås is best remembered for laying the foundations of the Swedish nobility with the Ordinance of Alsnö in 1280.
The ordinance also confirmed the principle of "oath laws", created by Birger Jarl, and which forbade, among other things, the kidnapping of women for wives.