Agathe Ursula Backer was born in Holmestrand in 1847, in a wealthy and art-loving home, as the second youngest of four sisters, all gifted in drawing and music. In 1857 she moved with her family to Christiania, where she studied with Otto Winther-Hjelm, Halfdan Kjerulf and Ludvig Mathias Lindeman. Between 1865 and 1867 she became a pupil of Theodor Kullak and studied composition under Richard Wuerst at the "Akademie der Tonkunst" in Berlin, where she lived together with her sister Harriet Backer. She won fame there with her interpretation of Beethoven's "Emperor" Concerto.