Memory
As indicated by the novel's title, the effects and consequences of memory form a central theme in The Longest Memory. The novel begins with an epilogue entitled "Remembering," in which Whitechapel professes his desire to erase from his mind his name, his history, and particularly his memory of betraying Chapel. Returning to the theme, D'Aguiar closes the novel with an epigraph called "Forgetting," in which he conveys Whitechapel's internal monologue in his dying moments. Whitechapel directly addresses the subject of memory, which he experiences as "pain trying to resurrect itself." Whitechapel says that "memory is longer than time," suggesting that while time may pass, the nature of memory means it is trapped in a perpetual present, a set of images and emotions recreated with every recollection. Whitechapel's struggle with memory reflects the lasting effects of slavery itself. While the institution of slavery in the United States may have been abolished in 1865, the memory of the historic injustice persists to the present.
Justifying Slavery
Throughout the novel, D'Aguiar writes through the voices of characters who seek to justify the institution of buying, selling, and abusing other human beings. The most vocal of the characters who advocate for the continuation of the slave trade is The Virginian's unnamed editorial writer. In his columns, the writer introduces issues around the treatment of slaves, including whether slave ownership is compatible with living as a good Christian. To answer this conundrum, the writer advocates for not forgetting that Africans are not equal in their humanity to white people. In another column, the writer suggests that white women being with black men presents several issues, but then neglects to articulate the rationale for his disgust. Ultimately, the writer's racist and economically self-interested bias that the slave trade needs to continue wins out over any logic.
Christianity's Incompatibility with Slavery
Another of the novel's major themes is the hypocrisy of Christians owning slaves. In the first chapter in his voice, Mr. Whitechapel identifies himself as a Christian and advocates for lenient treatment of his slaves, whom he believes capable not of possessing genuine human feelings but of emulating their masters' traits. Tone-deaf to his own hypocrisy, Mr. Whitechapel can think of himself as benevolent and therefore a good Christian because he is not as harsh with his slaves as other masters. Later in the novel, this hypocrisy is made more apparent when he is mocked by fellow plantation owners for preaching Christian ideals while allowing one of his slaves to be whipped to death. The subject of Christianity's incompatibility with slavery arises again when the editorial writer makes a convenient and specious distinction between economic needs and spiritual needs. In the writer's view, it is possible to extend Christian principles of good will to all men as long as one considers Africans and their descendants to be a primitive subspecies of human.
Abolitionism
Almost ambient in its presence, the movement for abolishing the slave trade sits in the background of The Longest Memory. Abolition arises as a theme in The Longest Memory most overtly when Sanders Senior writes in his diary that Mr. Whitechapel commented on "the clamor of the Abolitionists reaching new heights" at the slave auction block. Abolitionism isn't directly addressed again until one of the fellow plantation owners jokingly accuses Mr. Whitechapel of being an Abolitionist. D'Aguiar's subtle treatment of the theme speaks to how the concept of ending the slave trade went much further back than slavery's official abolition in 1865, and that many people within the South were opposed to slavery but their activism was either ignored, mocked, or actively fought against. With the views Lydia expresses, it is likely that she will advocate for the abolition of slavery, despite being a slave owner's daughter.
Violence
At the heart of The Longest Memory is an extreme act of violence that sparks trauma for the slave characters and debate for the white characters. Sanders lashes Chapel with a whip two hundred times—enough that Chapel dies from his wounds. The trauma of witnessing this act of violence prompts Whitechapel to adopt the detached look that Chapel takes on while being whipped and to renounce his name and history, as if he could forget the violence if he forgets everything else. Similarly, Whitechapel's great-granddaughter replaces her dreams of Africa with nightmares in which she relives witnessing Chapel's murder. Mr. Whitechapel reacts to Sanders' violence not with trauma but with disappointment, and he espouses to Sanders his views about treating slaves with more respect. Later in the novel, Sanders Junior and Sanders Senior reveal their shared belief that slaves must be treated with violence to keep them in line. Sanders Junior assimilates this belief in the importance of violence so completely that he admits in his internal monologue that he would have lashed Chapel even if he'd known Chapel was his half-brother.
Fear of Race Mixing
Through the subjects of interracial relationships and mixed-race offspring, D'Aguiar presents race mixing as another of the novel's major themes. In the racist, hierarchical cultural context of late-eighteenth-century Virginia, "anti-miscegenation" laws prohibited marriage between white people and people of color. In The Longest Memory, D'Aguiar conveys the double standard of the policy by showing Sanders Senior's (a white man) lenient punishment for raping and impregnating Cook (a black enslaved woman) against the disgust expressed by both The Virginian editorial writer and Lydia's older brother after they witness consensual relationships between black men and white women in the North. Unable to articulate what is so abhorrent about interracial couples, the editorial writer suggests the primary issue with interracial couples is that they have mixed-race offspring who have neither a white identity nor a black identity. In this facile justification for his prejudice, the editorial writer reveals his fear that interracial couples pose a threat to a racist society by blurring the socially constructed ethnic division.
Assimilating Notions of Inferiority
By depicting Whitechapel's extreme deference to authority, D'Aguiar conveys how the racist ideology that sought to justify slavery could spread to the slaves themselves. Having assimilated the notion that he, as an African, is biologically inferior to white people, Whitechapel remains obedient to his master. The slave owners see Whitechapel as a particularly valuable slave because he passes on the same repressive, hierarchical thinking to his descendants and fellow slaves. The theme of assimilating notions of inferiority is crucial to The Longest Memory, as it is this obedience to not only his master but to racial hierarchy that brings Whitechapel to betray Chapel in order to teach the boy a lesson in humility.