Eva Gustavson was born in Horten on the Oslo Fjord, in Norway. Her father, Oscar Gustavson, was a violinist-conductor at the National Theatre and later at Oslo Philharmonic Orchestra; her mother, Margit Gustavson (née Schwartz), played the piano and was an organist. Eva studied singing and dancing in her youth, becoming an accomplished tap-dancer, acrobat, and musician. She joined a traveling cabaret troupe in her late teens but was later advised to quit in order to pursue a career as an opera singer. She studied singing in Oslo with Bokken Lasson, Soffi Schønning and Signe Amundsen. During the early part of World War II, she entered the Stockholm Opera School in neutral Sweden on a scholarship where she studied under Adelaide von Skilondz. She was also mentored during this time by Kirsten