Without a strong protagonist, a book is rarely worth reading.
I went all the way through the Patrick O'Brian Aubrey-Maturin series twice, not because of my interest in the Napoleonic Wars (though there is some of that), but because Jack and Stephen are such memorable individuals.
Similarly The Lord of the Rings has a fine setting and great background material, but it would all mean very little without the quiet heroism of Sam, the fierce dignity of Theoden, and the sliminess of Grima Wormtongue.
I think this also explains why there are so few science fiction books I re-read; most of these books that I have read are more interested in a concept and a setting than in characters. There are, of course, wonderful exceptions, but they are indeed exceptions. Sadly, many fantasy books have ended up in the same pile for me of late. For every brilliantly drawn character, there are five Conan-knockoffs without the panache.
Give me an interesting character and I will read your book at least three times.