Ingri Mortenson (1904-1980) and Edgar Parin d'Aulaire (1898-1986) met at art school in Munich in 1921. Edgar's father was a noted Italian portrait painter, his mother a Parisian. Ingri traced her lineage back to the Viking kings. They married in Norway, moving to Paris, and then eventually to New York in 1929. The d'Aulaires published their first children's book in 1931, followed by three books steeped in the Scandinavian folklore of Ingri's childhood. The couple then turned their talents to the history of their new country. The result was a series of beautifully illustrated books about American heroes, one of which, Abraham Lincoln, won the them the Caldecott Medal. Finally they turned to the realm of myths, producing their beloved Book of Greek Myths .

The d'Aulaires worked as a team on both art and text throughout their joint career, publishing over twenty picture books, and receiving high critical acclaim for their distinguished contributions to children's literature. They were working on a new book when Ingri died in 1980 at the age of seventy-five. Edgar continued working until he died in 1986.