Sigrid Undset (20 May 1882 – 10 June 1949) was a Danish-born Norwegian novelist, awarded the Nobel Prize for Literature in 1928. Born in Denmark and raised in Norway, Undset had her first books of historical fiction published in 1907. Her opposition to Nazi Germany and its occupation of Norway during World War II led her to flee to the United States in 1940, but she returned after the war ended in 1945.

Her best-known work is Kristin Lavransdatter, a trilogy about life in Norway in the Middle Ages, portrayed through the experiences of a woman from birth until death. Its three volumes were published between 1920 and 1922. In 1924, she converted to Catholicism and became a lay Dominican.