Uncovered in the city of Uppsala one contained the remains of a man, a horse and a dog.
”This is a unique excavation, the last excavation of this grave type in Old Uppsala was almost 50 years ago,” Anton Seiler, an archaeologist at the National Historical Museums in Sweden, said.
”It is extremely exciting for us since boat burials are so rarely excavated. We can now use modern science and methods that will generate new results, hypotheses and answers.”
Only around 10 boat burial sites of this kind have been previously discovered. They were mainly found in the nearby provinces of Uppland and Västmanland.
In one of the newly discovered graves, archaeologists found personal items, including a sword, spear, shield and an ornate comb.
They said it was likely that they were for important members of society, due to their unusual burial.
”It is a small group of people who were buried in this way. You can suspect that they were distinguished people in the society of the time since burial ships in general are very rare,” Mr Seiler said.
A boat burial was a funeral practice which involved placing the deceased person in a ship, usually with gifts such as jewellery or sets of weapons and other objects.
The practice dates back to the Iron Age (around 550-800 AD) and the Viking Age (800-1050 AD), when people were usually cremated.
Boat burials are therefore thought to have been reserved for people of high status in society.
The graves were uncovered during an excavation at a vicarage in Old Uppsala last autumn. They were found beneath a cellar and a well dating from the Middle Ages.
Selected parts of the discovery will be put on display at the Gamla Uppsala Museum, Uppsala, and Stockholm’s Swedish History Museum.