Julian: A Christmas Story - a  review from The Guardian (U.K):

It's 2176 and, following a global technological collapse, the United States has reverted to a pre-electronic age of limited scientific understanding and Puritan social mores. The Sixty States of the Union are ruled by a coalition, the Church of the Dominion, headed by the autocratic President Deklan Comstock. The Union comprises three social groups: the aristos; the "leasing class" of tradesmen; and indentured labourers. Julian tells the rites-of-passage story of low-born Adam Hazzard and his friendship with the nephew of the president, the aristo Julian Comstock, relating how Adam's social conditioning is subtly undermined by Julian's heretical ideas: Darwinism, Einsteinism and DNA. The first-person narrative maintains an uneasy balance between reverence for the status quo and a fearful acknowledgment of the wonders of the past, while the text eschews sensationalism in favour of a thoughtful account of personal change and a skilled evocation of a feudal future.

As Robert J. Sawyer says of Wilson in the introduction to this fine novella, "He's sui generis: a hard-SF writer with the soul of a poet."