This is another fantasy that tries to break the mold by changing the setting from a conventional medieval Europe. The Acacian Empire, ruled by a brown-skinned family descended from a great sorcerer, is falling to bits, and readers are given front row seats for the chaos. The kindly king meets a predictably rapid violent end, and his four offspring are scattered to the ends of the earth in the wake of an invasion of pale-skinned, vengeful northerners. The scattering itself stretches the bounds of plausibility, and the development of the characters does so even more. One of the heirs becomes a peerless sword fighter within weeks of picking up a blade; another becomes a sort of pirate captain.
One review pointed out that the four children bear a passing resemblance to the Pevensies: noble eldest brother, shallow elder sister with archery skills, wandering younger brother, and brave younger sister. Fans of George R.R. Martin might notice parallels with Robb, Sansa, Arya, and Bran.
This book is better than Lewis's but not as good as Martin's. The world is less fully realized and the history invoked by the various characters is (intentionally?) confused and contradictory. Other aspects of the world are equally odd; entire societies seem to exist in unlivable conditions (what do the Numrek eat?), ageless wizards don't know how to heal despite their ability to preserve their own lives for millenia, and people seem unaware of a child slave trade that continually takes substantial numbers of children each year. The two eldest royals make choices near the end that are dictated by the requirements of plot rather than their characters as written.
This is not to say that it's a bad book; as fantasies go, it's a pleasant read. One of the best aspects of the book is its focus on the economics of empire and trade, with an emphasis on the power of merchants over rulers. Further volumes may yield less derivative plots and more consistent background. Recommended to fantasy fans.