- The novel's protagonist, Alexandra Bergson is a model of emotional strength, courage, and resolve. As the eldest child of the Swedish immigrant John Bergson, she inherits his farm and makes it profitable. Particularly suited to the toil of prairie life, she is a prototype of the strong American pioneer and an embodiment of the untamed American West.
- The youngest son of John Bergson, and the younger brother of Oscar, Lou, and Alexandra. Emil reaps the advantages of Alexandra's financial success: freed from the obligations of farm work, he is able to go to college and explore the world. He grows up tall, handsome, and athletic--a shining emblem of America's immense promise. Tragically, however, Emil falls in love with his flirtatious neighbor Marie Shabata; he is killed, along with her, by her husband, Frank.
- At the start of the novel, the Linstrums own the farm next to the Bergsons' homestead, and their teenage son, Carl, establishes a special bond with Alexandra Bergson. When Carl returns to the Divide as an adult, his friendship with Alexandra evolves into a deeper attraction. At the novel's end, they resolve to marry. Carl is a withdrawn, gloomy, pensive man, self-conscious, sensitive, and intelligent.
- The pretty, vivacious young Bohemian wife of Frank Shabata, and Emil Bergson's love interest. Marie's insistent cheer and friendly effervescence make her an easy friend for her neighbor Alexandra. But it also provokes the resentment of her husband, Frank, who seems determined to be unhappy. Near the novel's end, the jealous Frank kills both Marie and Emil.
- Marie Shabata's jealous, unhappy husband. When he seduced Marie away from her family, Frank Shabata was a handsome, dashing young man. Gradually, Frank becomes resentful and melancholy, and his marriage to Marie begins to unravel, leading her to pursue a relationship with Emil Bergson.
- The second son of John Bergson, and the brother of Alexandra, Oscar, and Emil. Lou is relatively intelligent, but he is also devious, small-minded, and vicious. He marries Annie Lee and settles into a life of scheming and small-time politics. He is less creative and flexible than Alexandra, and, like his older brother Oscar, he resents the relationship between Alexandra and Carl Linstrum.
- The oldest son of John Bergson, the younger brother of Alexandra, and the older brother of Lou and Emil. Oscar is a hard worker, but mentally sluggish and uncreative. Like his smarter brother Lou, he resents Alexandra for her financial success, her unconventional ways, and her relationship with Carl Linstrum.
- The patriarch of the Bergson clan, father of Alexandra, Oscar, Lou, and Emil. John Bergson had been a shipwright in Sweden, but became a farmer in the untamed, hardscrabble prairie lands of Nebraska. He recognizes the wisdom of his eldest child and leaves her as the caretaker of the farm he has fought so hard to cultivate out of the stubborn wilderness.
- Ivar is a deeply religious and slightly imbalanced elderly man. He distrusts civilization and behaves bizarrely around people, but seems to have an innate understanding of nature and animals. He becomes Alexandra's trusted servant.
- A French immigrant who is Emil Bergson's best friend. Amedee is clever, mischievous, kind-hearted, and jovial. His marriage to Angelique and the birth of their son seem to promise happiness and success. But Amedee's sudden death sets into motion the string of tragedies at the novel's end.
- The matriarch of the Bergson clan, wife of John Bergson, and mother of Alexandra, Oscar, Lou, and Emil. Mrs. Bergson is fat and unimaginative, but "a good housewife." Little else is known about her other than that she is of a lower social class than her husband.
- Lou Bergson's wife. Annie is a sharp, aggressive, petty woman who is obsessed with appearances. She is as intent as her husband on securing Alexandra's farm as an inheritance for their children. She is the mother of the charming and decent Milly, who becomes Alexandra's favorite niece.
- Despite Alexandra's dislike for her sister-in-law, Annie Lee, she has great affection for Annie's elderly mother. Mrs. Lee spends a long yearly visit in Alexandra's house, where she appreciates the reverence for old Swedish tradition.
- Amedee Chevalier's beautiful, graceful bride. Amedee's death punctures the optimism that her marriage and the birth of her son foster.
- The daughter of Lou and Annie Bergson, and Alexandra Bergson's favorite niece. Milly is intelligent and friendly, in contrast to her small-minded and devious parents.
- Alexandra's girlish, effervescent, loyal maid, who takes care of her during the difficult months after Emil's death. Signa marries Nelse Jensen.
- A man who works for Alexandra and eventually marries her maid Signa. He is glum and laconic, and his marriage to the cheerful Signa seems ill-fated.