This is the third volume in the new Polesotechnic League collection of Poul Anderson's works, and my second-favorite so far ("The Van Rijn Method" is still tops). In this volume, the merchant princes of the League begin to fall out among themselves and abandon the altruistic principles that have curbed their profiteering instincts over the last century or two. The Commonwealth gains more power during a war with an alien race called the Baburites, but eventually the two great centers of power begin to lose their grip on the worlds of humanity and its allies. Eventually it comes crashing down, and barbarian aliens to whom weapons were traded with no thought other than process take to space, and are able to penetrate to Earth itself, sacking and pillaging it repeatedly. Out of these ashes one man emerges to stop the chaos, and to bind together the remnants of human civilization. Manuel Argos becomes Emperor Argos I, and he builds the Argolid Dynasty and the Terran Empire, which quickly grows to encompass all the space formerly occupied by the League and the Commonwealth, and even beyond.
This book sees the first real description of the alien Ythrians, as well as some races that will become prominent in later volumes like the Merseians. In "People of the Wind" we see the development of a fascinating human-Ythrian colony, the first of its kind, and the similarities and differences between the two races. There is also an encounter between a descendant of Star Trader David Falkayn, and an ancestor of secret agent Dominic Flandry, who won't be born for another couple of centuries.
This volume is a great successor to the previous two, and makes me eagerly anticipate the next volume(s) that will see the zenith and decline of the Terran Empire and the emergence of Flandry.