It is rare that David Gemmell puts a foot wrong in his chosen genre of Historic/Heroic fiction and this is not the time. "The Hawk Eternal" is an excellent novel, fast paced, exciting and a great read.
This is the sequel to "Ironhands Daughter" and is the better book. The initial book being necessary to set the scene and introduce the characters required for this enjoyable romp where the highlanders vastly outnumbered take on the might of the Aenir (essentially Vikings) in a battle for the survival of their race and way of life.
This stands with many of David Gemmell's great novels as being a classic of heroic fiction.
I do not mean here to to disparage the works of the likes of George RR Martin, Joe Abercrombie or Conn Iggulden, who have all done a marvelous job in the same genre, I have enjoyed the majority of their books but Mr Gemmell's arse still sits firmly on the kings chair.