Kristin Lavransdatter by Sigrid Undset.
I had found an old copy of this book back around 1973; published in 1929 and translated by Charles Archer, et al, it features a purposely archaic language in an attempt to convey 14th century conversational style. The thing is... people in the "olden days" did not necessarily speak this way--their day to day speech was as "modern" and colloquial amongst themselves as ours sounds today. Despite this archaizing translation from the Norwegian by Mr. Archer, I enjoyed the book but, for some reason (lost to me in the mists of time), I never finished the novel back in high school. I probably read the first 100 pages or so.
Over the 2014 holidays I found a new translation by Tiina Nunnally who renders the language in a prosaic, unromantic manner while retaining the stark poetics of the Icelandic/Norse Sagas--as Ms. Unset intended. The book won a Noble Prize for good reason. I really enjoyed it and gobbled this 1100 page novel up within 2 weeks. If it takes the next reader a bit longer to read the book it'll be a time investment well worth it.
http://dannyreviews.com/h/Kristin_Lavransdatter.html