Sweden launched a probe on Wednesday to understand how eugenics, a theory on improving the human race used by Nazi Germany to justify the Holocaust, became broadly accepted in the Nordic state in the early 20th century.

Sweden is now known for its strong social welfare system and outspoken advocacy for human rights, but in the past it has experimented with social engineering. This led to abuses such as the forcible sterilization of around 60,000 women in 1936-76.

In 1922, the National Institute for Race Biology was founded with support from a range of political parties. The first of its kind in the world, the institute investigated whether race was a determining factor in illness or human character traits.

"An over-arching question is to find out more about the kind of society which could develop thinking on race biology and have scientifically accepted research in that area," Education Minister Leif Pagrotsky said in a statement.

The Living History Forum, a government body tasked with spreading "a deeper knowledge about crimes against humanity", was appointed to chart what is known about the Swedish history of eugenics and, if necessary, do more research on the issue.

The Forum was founded by Social Democrat Prime Minister Goran Persson's government in 2003, mainly to improve public knowledge about the Holocaust in which around 6 million Jews were killed by the Nazis and their allies from 1933-1945.

The Swedish eugenics research body was merged in the 1950s with a university genetics department.

Other negative aspects of Sweden's past have come to light recently. The government this month promised an official inquiry into claims by thousands of Swedes of physical abuse and cruel treatment in state children's homes for decades from the 1950s.