Viefers was born on 28 March 1970 in Orsoy, Germany. She moved to Norway as a teenager, but retains her German citizenship. She did all of her studies at the University of Oslo, earning a bachelor's degree in 1992, a master's degree in 1993, and a doctorate (Dr. Sci.) in 1997. Her dissertation was Field theory of anyons and the fractional quantum Hall effect.