African American Experience in the 1950s
Frank returns from serving in an integrated military only to find that the home he is returning to is still mired in segregation. This is Jim Crow America, and though many Americans wax poetic about the good old 1950s, Morrison wants to show that it was far from ideal, especially for Black people. Through both Frank and Cee's stories, as well as those of peripheral characters—the old man who won't leave his home, Lenore's first husband, the couple on the train, Billy's son, etc.—we see the deleterious effects of white supremacy and systemic racism.
The Eugenics Movement
The eugenics movement was prevalent in the early 20th century and its philosophy entailed the manipulation of the population under the guise of science; proponents of eugenics believed that in order to strengthen the overall population, those with supposedly undesirable ethnic traits ought to be prevented from reproducing. Dr. Beauregard conducts "experiments" on poor and Black women claiming that he has an interest in wombs; this is really done to sterilize them so they will not be able to reproduce and bring more "undesirable" people into the world. Though it is not well-known, the eugenics movement is part and parcel of the white supremacy that dominated the 1950s.
Facing the Truth
Both Frank and Cee need to face up to the ugly truths of their lives before they are able to make peace with themselves and move on. They have been greatly affected by their past; in particular, Frank's present is overshadowed by his experiences in Korea. He suffers from extreme post-traumatic stress disorder and episodes that are so severe that he has to be hospitalized in a mental institution. This is caused by a memory of a Korean girl being shot in the face by a soldier after she sexually aroused him. It is not until he is able to admit and confront the fact that he was the soldier in question that he is able to move on with his life and become a better person.
Similarly, having been long troubled by the death of a man in a fight that they witnessed as children, Frank and Cee find the man's shallow grave and dig up his body, wrapping it in a quilt that Cee has made as a makeshift coffin, and re-burying him. This mark of respect atones for what they have done with their lives and what they have witnessed, again allowing them to move ahead and also to make their peace with the town of Lotus again.
Home
Unsurprisingly, this is a prominent theme in the novel. What is home? Where is it? How do you know you've found it? For Frank and Cee, home was always an elusive concept, and they sought it with each other, in the military, in jobs, with lovers, or simply tried to pretend it wasn't necessary. Much of the novel explores their journey to home, both literally and figuratively. In the end, that home is the same location it was when they were children—Lotus—but they can now truly welcome it as a home because of the way they arrive there—ready for healing, ready to work through trauma, ready to see themselves and each other as whole, unified beings.
Community
Cee's healing comes through community—specifically, the community of women in Lotus. Through their unyielding, fierce love and tenacious curative measures, Cee is able to overcome the physical and mental wounds perpetrated on her by the doctor. It is their collective succor that heals her, not a stint in a hospital. It is their shared pain, their shared faith that provides the ballast for Cee. Morrison suggests Black, feminine spaces are restorative and sustaining, especially in contrast to white patriarchal ones.
Being Saved, and Saving Oneself
Frank has always been Cee's protector, giving her advice and saving her from any threats that come her way. Yet he cannot always be in that role, and his stint away from her in Korea makes clear the shortcomings of always having someone else solve your problems for you. Cee has to learn self-worth, resilience, and independence on her own. She can love Frank and live with him, but it has to be as equals. One of the most valuable lessons the women of Lotus teach her is that it is better to save oneself than to be saved.
Trauma
Both Frank and Cee are deeply traumatized by their childhoods and the events of their young adult lives. They are burdened by physical and mental wounds, which lead them to engage in deleterious behaviors and thought patterns. Their healing processes include facing repressed memories; finding a real home; learning to love oneself and to save oneself; finding an alternate family; atoning for their mistakes; reclaiming their bodies; and returning to a communal Black space.