Rølvaag's authorship and scholarship focused on the pioneer experience on the Dakota plains in the 1870s. His most famous book was
Giants in the Earth, part of a trilogy. The novel realistically treats the lives and trials of Norwegian pioneers in the
Midwest, emphasizing their battles with the elements. The book also portrays the trials of loneliness, separation from family, longing for the old country, and the difficulty of fitting into a new culture.
Giants in the Earth served as the basis for
an opera by
Douglas Moore and
Arnold Sundgaard that won the
Pulitzer Prize for Music in 1951. ==Honors and awards==