Researchers in Iceland have managed to recreate part of the genome of a man who died in 1827, despite not even knowing where his final resting place is. Published in Nature Genetics, the study highlights not only the impressive power of modern genetics, but also the remarkable story of Hans Jonatan, who was born a slave in the Caribbean but died a free man in Iceland.

The reason that scientists have been able to recreate the DNA from someone who died almost 200 years ago is down to two separate factors.

The first is related to the astonishing record-keeping in Iceland, where genealogical databases have been kept since people first settled on the island some 1,200 years ago. Since then, the inhabitants of Iceland have kept meticulous records of everyone living there, allowing them to create incredible family trees going back to the very beginning. This means that the researchers knew exactly who Jonatan’s descendants were.  

The second factor that allowed this recreation is simply Jonatan’s astounding history.  

Jonatan was born on a plantation in the then Danish colony of St Croix in the Caribbean to a Danish man and a black slave called Emilia Regina in 1784. When he was five, Jonatan and his mother were taken by their white owners back to Denmark, where they continued to serve the couple. At the age of 17, however, Jonatan escaped and joined the Danish Navy. During this time he fought in the Napoleonic War and received recognition.

On returning to Denmark, Jonatan tried to free himself, arguing in court in 1801 that as slavery was now illegal in Denmark he should not have to serve the family that still by law owned him. The court ruled against him, saying that as he was born in St Croix where slavery was still legal, he should be repatriated. Jonatan had other ideas and escaped once more.

A few years later, Jonatan had made his way to Iceland, appearing in a small fishing town known as Djúpivogur. He married an Icelandic woman and eventually had three children. What is most important here, however, is that he is thought to have been the first person of African descent to have settled in Iceland, and was so for at least another hundred years.

This means that the DNA Jonatan inherited from his mother was completely distinct from all other inhabitants, and was easily traceable down his family tree to the 788 known surviving Icelandic descendants, 182 of which were sampled for the study. This allowed the researchers to reconstruct 38 percent of Emilia’s genome and 19 percent of Jonatan’s, revealing that Emilia likely came from Benin.

Because of this unique set of circumstances, this method is unlikely to be much use for other dead people, but it's an incredible achievement nonetheless.