Rölvaag immigrated to the United States in 1896 and was naturalized in 1908. Educated at St. Olaf College, Northfield, Minn., and the University of Oslo, Norway, he spent most of his life at St. Olaf as a teacher of Norwegian language and literature and the history of Norwegian immigration. He wrote in Norwegian, the language in which his works were originally published, and worked closely with the translators of the English versions.

Rölvaag gave epic sweep to his picture of pioneering but also deplored its cost in human values. A founder of the Norwegian-American Historical Association in 1925, he tirelessly urged immigrants to retain their customs, their speech, and their church, believing that American society would be the richer. Two novels, I de dage (“In Those Days,” 1924) and Riket grundlæges (“The Kingdom Is Founded,” 1925), were translated as Giants in the Earth (1927), his best novel, representing the positive aspects of pioneering in the character Per Hansa, the negative aspects in his wife Beret. Peder Victorious (1929) and Their Father's God (1931) continued the story to the second generation.