If you are interested in the historical background to Mel Gibson's Braveheart, this might be the book you want. It turns out that Mel Gibson got the name of William Wallace right, and his stubborn refusal to yield to Edward Longshanks right, but not much else.
Scotland had enjoyed almost a century of internal peace under the kings David I, Alexander II, and Alexander III. When Alexander III died without a male heir the Scottish nobles became uneasy: even if Scotland had stabilized under "the Good King" Alexander, it was still an unruly place with ambituos noblemen and aggresive norse lords in the north and west. When his daughter (the maid of Norway) died in Orkney 1290, the [...] hit the fan - now the throne was up for grabs.
This book describes the old-fashioned political system of the Scottish kingdom, and why it became so vulnerable in a succesional crisis. It then continues with the complex political games in the crisis of the succesion - nobles switched allegiance as often as we change underwear. It is an interesting fact how international the Scottish crisis was: claimants to the throne came from Norway, Flanders, France, and England. The political intruiguing involved not only England and Scotland, but also Gwynnedd, Irish sub-kings, France, Holy Roman Empire, Scandinavia, and the Papal curia. William Wallace turns out to have been a comparatively minor character in all this.
Sometimes the sheer number of names is overwhelming, and there is a lack of pictures. The writing is a bit dry, and the subject gets a very, almost too, scholarly treatment.
The main strengths of the book, I think, are that the author thoroughly describes the causes of the political crisis that led to the wars and that he puts them into their European context.