My thesis explores why beauty became so much more important in nineteenth-century Britain, especially for marriageable young women in the upper and middle class. My argument addresses the consequences of that change in the status of beauty for plain or ugly women, how this social shift is reflected in the novel, and how authors respond to the issue of plainer women and issues of their marriageability. I look at how these authorial attitudes shifted over the century, observing that the issue of plain women and their marriageability was dramatized by nineteenth-century authors, whose efforts to heighten the audience's awareness of the plight of plainer women can be traced by contrasting novels written early in the century with novels written mid-century. I argue that beauty gained more significance for young women in nineteenth-century England because the marriage ideal shifted, a shift which especially influenced the upper and middle class. The eighteenth century brought into marriage concepts such as Rousseau's "wife-farm principle" the idea that a man chooses a significantly younger child-bride, mentoring and molding her into the woman he needs. But by the end of the century the ideal of marriage moved to the companionate ideal, which opted for an equal partnership. That ideal was based on the conception that marriage was based on personal happiness hence should be founded on compatibility and love. The companionate ideal became more influential as individuality reigned among the Romantics. The new ideal of companionate marriage limited parents' influence on their children's choice of spouse to the extent that the choice lay now largely with young men. Yet that choice was constrained because young men and women were restricted by social conventions, their social interaction limited. Thus, according to my reading of nineteenth-century authors, the companionate ideal was a charade, as young men were not able to get to know women well enough to determine whether or not they were compatible. So instead of getting to know a young woman's character and her personality, they distinguished potential brides mainly on the basis of appearance.