The title character of the novel, Don Quixote is a gaunt, middle-aged gentleman who, having gone mad from reading too many books about chivalrous knights, determines to set off on a great adventure to win honor and glory in the name of his invented ladylove, Dulcinea. Don Quixote longs for a sense of purpose and beauty—two things he believes the world lacks—and hopes to bring order to a tumultuous world by reinstating the chivalric code of the knights-errant. Initially, Don Qui-xote's good intentions do only harm to those he meets, since he is largely unable to see the world as it really is.

As the novel progresses, Don Quixote, with the help of his faithful squire Sancho, slowly distinguishes between reality and the pictures in his head. Nonetheless, until his final sanity-inducing illness, he remains true to his chivalric conception of right and wrong. Even though his vision clears enough to reveal to him that the inns he sees are just inns, not castles as he previously believed, he never gives up on his absolute conviction that Dulcinea can save him from all misfortune. Furthermore, even when Don Quixote must retire from knight-errantry, he does so in the spirit of knight-errantry, holding to his vows and accepting his retirement as part of the terms of his defeat at the hands of the Knight of the White Moon. Despite his delusions, however, Don Quixote is fiercely intelligent and, at times, seemingly sane. He cogently and concisely talks about literature, soldiering, and government, among other topics.

No single analysis of Don Quixote's character can adequately explain the split between his madness and his sanity. He remains a puzzle throughout the novel, a character with whom we may have difficulty identifying and sympathizing. We may see Don Quixote as coy and think that he really does know what is going on around him and that he merely chooses to ignore the world and the consequences of his disastrous actions. At several times in the novel, Cervantes validates this suspicion that Don Quixote may know more than he admits. Therefore, when Don Quixote suddenly declares himself sane at the end of the novel, we wonder at his ability to shake off his madness so quickly and ask whether he has at least partly feigned this madness. On the other hand, we can read Don Quixote's character as a warning that even the most intelligent and otherwise practically minded person can fall victim to his own foolishness. Furthermore, we may see Don Quixote's adventures as a warning that chivalry—or any other outmoded set of values—can both produce positive and negative outcomes. Given the social turmoil of the period in which Cervantes wrote, this latter reading is particularly appealing. Nonetheless, all of these readings of Don Quixote's character operate in the novel.

Sancho Panza

The simple peasant who follows Don Quixote out of greed, curiosity, and loyalty, Sancho is the novel's only character to exist both inside and outside of Don Quixote's mad world. Other characters play along with and exploit Don Quixote's madness, but Sancho often lives in and adores it, sometimes getting caught up in the madness entirely. On the other hand, he often berates Don Quixote for his reliance on fantasy; in this sense, he is Don Quixote's foil. Whereas Don Quixote is too serious for his own good, Sancho has a quick sense of humor. Whereas Don Quixote pays lip service to a woman he has never even seen, Sancho truly loves his wife, Teresa. While Don Quixote deceives himself and others, Sancho lies only when it suits him.

Living in both Don Quixote's world and the world of his contemporaries, Sancho is able to create his own niche between them. He embodies the good and the bad aspects of both the current era and the bygone days of chivalry. He displays the faults that most of the sane characters in the novel exhibit but has an underlying honorable and compassionate streak that the others largely lack. Sancho does not share Don Quixote's maddening belief in chivalrous virtues, but he avoids swerving toward the other extreme that equates power with honor. Though Sancho begins the novel looking more like the contemporaries against whom Don Quixote rebels, he eventually relinquishes his fascination with these conventions and comes to live honorably and happily in his simple position in life. He therefore comes across as the character with the most varied perspective and the most wisdom, learning from the world around him thanks to his constant curiosity. Though Sancho is an appealing character on many levels, it is this curiosity that is responsible for much of our connection with him. He observes and thinks about Don Quixote, enabling us to judge Don Quixote. Sancho humanizes the story, bringing dignity and poise, but also humor and compassion.

Through Sancho, Cervantes critiques the ill-conceived equation of class and worth. Though Sancho is ignorant, illiterate, cowardly, and foolish, he nonetheless proves himself a wise and just ruler, a better governor the educated, wealthy, and aristocratic Duke. By the time Sancho returns home for the last time, he has gained confidence in himself and in his ability to solve problems, regardless of his lower-class status. Sancho frequently reminds his listeners that God knows what he means. With this saying, he shows that faith in God may be a humanizing force that distinguishes truly honorable men, even when they have lower-class origins.

Dulcinea del Toboso

The unseen, unknown inspiration for all of Don Quixote's exploits, Dulcinea, we are told, is a simple peasant woman who has no knowledge of the valorous deeds that Don Quixote commits in her name. We never meet Dulcinea in the novel, and on the two occasions when it seems she might appear, some trickery keeps her away from the action. In the first case, the priest intercepts Sancho, who is on his way to deliver a letter to Dulcinea from Don Quixote. In the second instance, Sancho says that Dulcinea has been enchanted and that he thus cannot locate her.

Despite her absence from the novel, Dulcinea is an important force because she epitomizes Don Quixote's chivalric conception of the perfect woman. In his mind, she is beautiful and virtuous, and she makes up for her lack of background and lineage with her good deeds. Don Quixote describes her chiefly in poetic terms that do little to specify her qualities. She is, therefore, important not for who she is but for what her character represents and for what she indicates about Don Quixote's character.