I'm on Tapatalk and can't see the poll, but from a quick scan of the thread, it looks like this book is out of the running...
Nevertheless, for future reads, I cannot recommend "The Greatest Knight" highly enough. Chadwick is an outstanding writer of history, and this is her masterpiece. It is followed by "The Scarlet Lion", which while not necessary, is just as good and a great follow - up you won't want to miss. It covers the latter years of his life and family, until his death.
I read it and the three following (2 about his children) twice within 3 months of buying, and everyone I rec'd it to loved it. When I saw the "Books you can't put down" thread, it was one of the first that came to my mind.
I would not classify it as a romance, but historical fiction /biography of the truly fascinating and adventuresome life of William Marshall, who was called the Greatest Knight in the realm of Britain.
He began as a relative nobody, but wound up a highly respected earl, serving the Plantagenets from Henry II through Henry III (including Richard the Lionheart and John). He was regent of England for young Henry III.
There is some romance in that his very happy marriage is covered, but otherwise, I'd only classify it as romance of the Ivanhoe type.