In Charles W. Chestnutt's story "The Wife of His Youth," the Blue Veins were people of color who had joined together to form a social club in an unnamed Northern city a few years after the Civil War. The club had an official name, but most people inside and outside its membership called the club "The Blue Vein Society" and people who belonged to the group "Blue Veins." The group was controversial within the black community in this city. The nickname had originally been given as a pejorative; someone who didn't belong to the club made the satirical charge that one had to have skin light enough to be able to see "blue veins" in order to be accepted into the group. While this was not technically true, those who belonged to the group, "by accident, combined perhaps with some natural affinity," tended to have more white ancestry than black. A large majority of the group had been freeborn; only a few former slaves were part of the society. This exclusive nature of the social club caused those who hadn't been accepted for membership to be jealous of the group and speak ill of it--but only until such time as their membership was accepted. Then they insisted the group performed a much needed function for blacks in their city.
That function was to "establish and maintain correct social standards" among blacks, an important function because many blacks, due to poverty, lack of opportunity, and discrimination, had not had the natural opportunities for cultural improvement that their white counterparts had. In general, the group existed to provide entertainment to their members of a more sophisticated variety than might be readily available to them. Thus Mr. Ryder, the "dean" of the group and a very influential member, is in the process of planning a ball at the beginning of the story. Mr. Ryder has a passion for poetry, and such pursuits were in sync with the objectives of the Blue Vein Society. Part of the society's goals, in Mr. Ryder's opinion, however, could seem racist by some people's understandings. He felt it was the duty of those who had mixed blood to continue to preserve their level of whiteness and not allow their progeny to become more black, which "would be for us a backward step," in Mr. Ryder's view. The club, therefore, provided ways for the blacks of mixed blood to associate with their own kind rather than with those with a greater degree of blackness. Of course, these values of Mr. Ryder face a stern test when he is confronted by the wife of his youth.
Early in the story, Chesnutt says this of the Blue Veins: “The original Blue Veins were a little society of colored persons organized in a certain Northern city shortly after the war.”
They were an organization committed to promoting certain standards of behavior in the African American community, and improving its situation. Many of the Blue Veins were mixed race, some light enough that, Chesnutt tells us, they were more white than Black.
Their purpose in the story, then, was to uplift African Americans in the post-slavery period. Their purpose for Chesnutt is also to comment on the form that this uplift took. You’ll notice that the group’s leaders are conservative, and Mr. Ryder, one of the leaders, took pride in memorizing and reciting great English poets. This gives a model of how educated/respectable African Americans should act.