After Willie's funeral, Jack returns to Burden's Landing because he can no longer to stand to be in the capital and he wants to see Anne, who collapsed after Adam's funeral. He recalls her expressionless mourning at the funeral. He also remembers that a young photographer shoved a camera in her face to get a photo. Jack took him aside and called him a son-of-a-bitch, and the photographer criticized him for having worked for Willie.
At the Landing, Jack and Anne spend a great deal of quiet time alone together. Eventually, Jack starts to wonder who telephoned Adam about Anne's relationship. One day, he asks Anne, but she says she does not know.
Right after that, Jack returns to the capital, where he tries to find Sadie Burke. An operator informs him that she was committed at Millett Sanatorium. Jack meets her there, and she seems very tired. Sadie says that she checked herself in to get rest. Jack asks her who told Adam about Anne's and Willie's affair, and she reveals that it was the work of Tiny Duffy, who ascended to the governorship upon Willie's death. Sadie then says that she was the one who told Duffy to do it. After Willie's death, Sadie felt no guilt until Duffy congratulated her and said that the two "might sure get along" (566). Disgusted by her role in the affair, she immediately left the capital.
Sadie is horrified to have had to reveal her role, but she also is glad to have told someone. Jack, meanwhile, feels somewhat cleansed by the revelation. He tells her that he wants to get back at Duffy, and she agrees to do what she can to help, even though she fears they could not make anything legally stick.
Jack visits Duffy at the Governor's mansion, where Duffy offers him a position as a political operative in the same capacity he fulfilled under Willie. Jack rebuffs Duffy and insults him to his face, then threatens to go public with what he knows about Willie's death. He feels heroic in his act.
Later, Jack receives a letter from Sadie, who has left the state permanently. She has advised him to leave the issue alone, since it could only be used for revenge against Duffy. She nonetheless offers to help with whatever Jack decides to do. From Sadie's letter, Jack feels less heroic and comes to the realization that he remains a part of the system of corrupt politics that brings so much destruction.
Jack spends a short period avoiding Anne and trying to forget the matter. He runs into Sugar-Boy in the library, and he comes up with the idea of telling him of what Duffy did, knowing that Willie's faithful bodyguard would exact revenge. But when he sees Sugar-Boy's murderous expression, Jack becomes frozen, and he tells him that he does not know who killed the Boss.
Three months later, Jack decides to visit Lucy Stark. Her son Tom died of pneumonia earlier in the year. Lucy has adopted the alleged child of Tom and Sibyl Frey, and she insists that the baby is her son's, because "it looks like him" (584). She has named the baby Willie. She insists that her husband was "a great man ... I have to believe that" (586).
Jack returns to Burden's Landing in the summer at his mother's request. She tells him that she has left her husband Theodore in part because of the death of her true love, Judge Irwin. The next day, Jack's mother leaves Burden's Landing permanently. She tells Jack that she will let Theodore have the house. Right before she leaves, Jack's mother asks him what he went to see Judge Irwin about just prior to his suicide. Jack lies and says that they talked about his poor health.
At last, Jack visits Anne and reveals to her that Judge Irwin was his father. He tells her, "if you could not accept the past and its burden, there was no future" (598).
Writing from the present, Jack concludes the narrative, framing it as one involving both himself and Willie Stark. He writes that he has stopped believing in the Great Twitch and has accepted responsibility for the things that have happened around him. He mentions Hugh Miller, Willie's former Attorney General, and indicates that he will work for Miller when the good man returns to politics.
Jack is now living in Judge Irwin's home with his invalid non-biological father Ellis Burden. He is married to Anne and is working on finishing the book he began as a graduate student about Cass Mastern. By summer of 1939 he expects to have left Burden's Landing with Anne for good, and to "go out of the house and go into convulsion of the world, out of history into history and the awful responsibility of Time" (602).
Jack Burden had spent his entire life avoiding his past: his failed relationship with Anne Stanton, the traumatic departure of his father at a young age, and the detachment set by his mother's subsequent remarriages. He had fallen into periods of great sleep, studied history without understanding it, and aimlessly followed a charismatic leader. Only after a series of earth-shattering events and realizations could Jack be jolted out of his lifelong ennui.
First, Jack recaptured his past. He learned the true identity of his father and the story behind his assumed father's departure. He thus came to sympathize and not resent Ellis. Jack also realized a newfound respect for his mother, whom he once thought to be detached and incapable of love. Her ability to reject the men who had dominated her life out of true love helps inspire Jack to reconcile with Anne.
Second, Jack witnessed the destructiveness of immorality and the bravery that followed redemption. He witnessed the jealousy and corruption that led, through a series of events, to self-destruction. He now has come to understand the effects that one's actions have on others and on oneself. He has come to respect his biological father's bravery in refusing to relent in the face of blackmail.
Finally, through investigating the matter of Willie's murder, Jack has come to realize his own responsibility and guilt. At first, he is relieved by the knowledge that Tiny Duffy had placed the call that resulted in Adam's homicide. But then he is horrified to realize that he was an integral part of the complex system of corruption that killed Willie. The fact that Tiny Duffy was so sure that Jack would work for him proved to Jack that despite his cynical pride, he had been a co-conspirator in Willie's death through his inextricability from the entire process of events. Instead of refusing to dig up dirt in order to blackmail people, Jack agreed to do so with no emotional regard for the consequences of his actions, falsely assuming all along that a lack of evil intent would make him innocent.
Jack acts on his realization by deciding not to use the knowledge of what Duffy had done in order to take him down later. His encounter with Sugar-Boy is his first moral test, and if Jack were to have used Sugar-Boy to put out a hit on Duffy, he would have been no better than Duffy himself. At last, Jack Burden has truly changed, now that he has accepted his past and is beginning to take responsibility for what he has done and will do.
With all of this now behind him, and with his new understanding of agency and responsibility, Jack is able to reconcile with Anne by explaining how he has come to accept his past.
Jack ends up with two people to look up to, Hugh Miller and Lucy Stark. Both represent reconciliations between the values of the Old South and the New South. Hugh is as forceful and as devoted to fixing the political system as Willie, yet he stays away from any element of corruption. Lucy espouses plain moral values of the Old South such as faith and humbleness, yet she is averse to the code of honor that caused Adam to assassinate her husband. As for Willie himself, he appears to have been reincarnated as an innocent baby, who will grow up in the humble country, just as his namesake once did. Ultimately, this is the symbol or reflection of Willie's redemption--a child born of sin but surrounded by infinite hope. Raising the child after all she has endured, Lucy represents the regenerative ability of the Old South's way of life in aftermath of great crisis.
At the end of All the King's Men, Jack Burden is at last capable of accepting the past and its burden. Consequently, he has realized the effects his actions have on others, and now he takes responsibility for what he does. His more realistic understanding of cause and effect has also given Jack the direction in life that he has always lacked. He now understands why Cass Mastern had to repent for what he did, so Jack is now capable of finishing his thesis. He finally is able to leave Burden's Landing permanently.