StringerBell wrote: Nie było wcale mi trudno. (Not sure if that's right, it popped into my mind as soon as I wrote the English sentence).
It isn't incorrect, it even doesn't sound weird, but I do not think that a native speaker would use it. I asked my wife (my advisor in most language-related cases), and she immediately said what I also had in mind Nie było to wcale trudne. You may also use "ciężkie" (heavy) in this case. That word means difficult or heavy depending on context.
hedgehog.chess already explained most o what I was going to say about the book. I would like only to add that the language may be little old, but children read it in primary school and understand it. Sienkiewicz was writing in the times when there was no Poland. He created some unforgettable books describing Polish golden era (or rather silver) - 17th century - Trylogia with Ogniem i mieczem, Potop and Pan Wołodyjowski. Many young people were reading them, and when the time has come they volunteered to fight for Polish independence during and after the First World War. That was Sienkiewicz's goal, and that is why his works are so important in Polish history.
Sorry for this lecture on the topic, but History is not only my work but also my love Just behind my wife and children of course.