I read and enjoyed the first book in the series, Snowfall, so I hunted down the other two. It's been hundreds of years since a change in Jupiter's orbit brings on a massive ice age, and modern civilization collapses. The action takes place in North America, and a variety of regional communities have grown up. I really like all the different societies, and the characters he creates. In the first book, I had some trouble believing that the ecology/economy of the Trappers would work, and became happier as they migrated south. In the second book, I found the Middle Kingdom and North Map Mexico to be believable, and the sweeping action riveting. The third book takes the action through the Indian* tribes up to DNA-twisting science-fictionally-magical Boston.

The second and third books open about 20 years after the end of the previous book, with a protagonist who is a young man now and was a baby at the end of the earlier book -- a most unusual way to continue a series, and quite satisfying. The second book is war, and politics, between three regions. It's rather grounded and realistic, thought there are some fantastic elements. The third book is a quest. The action is one long trip, probably suicidal, to strike a blow for justice. This book takes us into the strangeness that Boston has created, and goes through other wonders. The "farmers" are eerie, the animalistic Boston Guard is astonishing, and the climbing sequence is fantastic. I did have a bit of trouble in the 3rd book, keeping suspension of disbelief down about the Boston economy.

While each book is quite different, and probably could be read on its own, I think you'll get more out of them by reading them in order, if only due to the handful of continuing characters. If I hadn't read them in order, I wouldn't have been on the edge of my seat, terrified, as Martha traveled from her home to the Island. Yowza.

There are wonderful, strong women characters: Catania the Trapper doctor; Patience the slightly mad, rather blood-thirsty, flying Bostonian meddler; Queen Joan of the Middle Kingdom, who was Crazy Joan of the Trappers, and likely to say "Fuck, let's get this over with" on ceremonial occasions; and Nancy the sort-of fox; Charmian is critical to Sam Monroe's greatest military victory.

*They're kinda, sorta Indian tribes.