Justice and revenge, which are central themes in True Grit, play minor roles in The Dog of the South, while restlessness, a lesser theme in True Grit, emerges as the main theme in both The Dog of the South and Gringos. Mattie Ross, a devout Presbyterian who frequently quotes the Bible, firmly believes in the principle of "an eye for an eye." Her drive for vengeance is unwavering, and she insists that Rooster Cogburn deliver precisely what they agreed upon for tracking down her father's killer. She seeks justice in Fort Smith, where her father was murdered, but above all, she demands that Tom Chaney pays with his life if a formal trial for murder is not possible. Her determination rivals that of Chillingworth in The Scarlet Letter (1850) or Ahab in Moby Dick (1851), as she relentlessly pursues satisfaction. In contrast, Ray Midge and Norwood Pratt also seek satisfaction, but they are easily sidetracked and possess far more forgiving natures than Mattie. Their characters resemble Tom Jones or Huck Finn more than the obsessive figures created by Hawthorne and Melville.

While restlessness is a minor theme in True Grit, it serves as a primary theme in The Dog of the South and Gringos.

Ray and Norwood are capable of feeling love, an emotion that Rooster Cogburn might have inspired in Mattie. However, the theme of love takes on a more significant role in Norwood and The Dog of the South, and it occasionally appears in Masters of Atlantis.

Although Mattie might hold back her feelings, she experiences none of the spiritual decay—a theme heavily explored in both "Dog of the South" and "Masters of Atlantis."

Similar to the other main characters in Portis's novels, Mattie has to navigate a world teeming with swindlers, fraudsters, and eccentrics. Consequently, a central theme connecting all of Portis's works is the idea of outlawry and nonconformity.

With a deft touch of humor and sharp, believable dialogue, Portis skillfully avoids falling into sentimentality, instead crafting a vivid celebration of his beloved Arkansas. Through his setting and characters, he highlights the enduring values and virtues of America, a nation resilient enough to cling to the mythic ideals of integrity and independence, even as reality frequently challenges these dreams. Portis manages to affirm a vision of noble and heroic America, while also unmasking the less glamorous sides of nobility and heroism.

For instance, LaBoeuf, who might initially appear as the embodiment of noble qualities, is portrayed as merely an efficient, yet somewhat narrow-minded, policeman. Meanwhile, Cogburn, the figure of heroism, emerges as a tenacious vigilante, a man whose stubborn resolve defines his character. Despite their flawed depictions, the narrative intertwines their fates in a manner that underscores the complementary nature of their actions. LaBoeuf's noble deeds ultimately save Cogburn's life, while Cogburn's heroic efforts ensure Mattie's safety, creating a tapestry of intertwined destinies that celebrate the complexity of American virtues.

The period following the Civil War was marked by significant transition, where notions of nobility and heroism were put to the test. Set against this backdrop, Charles Portis illustrates how these ideals evolved, yet remained intact. This era, spanning the two decades after the war, saw the old century segue into a new one, with figures like Mattie symbolizing the resilient spirit of America—pragmatic and God-fearing. She navigates both the familiar and the novel landscapes with equal poise.

Arkansas serves as a meeting point for the remnants of the Old South and the Old West, where traditional ways of life transform, yet the unyielding spirit of these regions endures. The conclusion of the Reconstruction era in 1877,...