If you're in need of a nice long historical fiction novel to read over your holiday break, I can do little more than to recommend Kurt Andersen's Heyday (Random House, 2007). It's a sprawling, adventuresome look at American culture of the late 1840s, with its utopian communities, growing cities, racial and social tensions, and endless temptations.
Andersen's major characters - memorable all - include erstwhile English émigré Benjamin Knowles, freethinking actress Polly Lucking and her former soldier brother Duff (whose troubles neither began nor ended with traumas sustained during the war with Mexico), plus the carousing Timothy Skaggs, a fascinating writer/photographer/astronomer (whose earlier adventures would make a delightful prequel, should Andersen feel up for it). This quartet, once united, find themselves caught up in a series of cross-continental adventures which, improbable as they may be, make for a fun read (after a rather slow start to the book, it picks up pace quickly).
I enjoyed the cameo appearances by various historical figures (including Poe, Darwin, Pinkerton, Tocqueville, and Lincoln's law partner James Herndon, among others), although as they kept happening the effect wore a little thin. I do wish that Andersen had included a note about his research (obviously extensive) and how he incorporated the historical details into his story.
All in all, an absorbing and detailed book, which I enjoyed a great deal.