So when reformers started insisting, first, that bishops could not be chieftains, and then that chieftains could not control tithes, and then that they could not occupy church lands, Icelandic politics was thrown into turmoil. Snorri rode this wave successfully for a while, but eventually he angered too many people, and a faction of his relatives attacked and killed him. This left a power vacuum into which the kings of Norway soon stepped, ending the island's independence for 600 years.
Brown is a good guide to all of these complications, and to the many crazy characters who inhabited Snorri's world. Unfortunately she is not a good guide to either Snorri's relationship with the Norse myths and the poetic tradition, or to his influence on later writers. But you can't have everything, and if you are curious about Snorri Sturluson and the end of Viking Iceland, I know of no better place to start.