Icerigger

When a botched kidnapping strands a mismatched group of travelers -- a salesman, a professional adventurer, a tycoon and his daughter, a schoolteacher, and the kidnapper himself -- on the frozen, wind-scoured world of Tran-ky-ky, survival means throwing in with the local feudal society that finds them. That society is bracing for the Horde, a nomadic swarm that descends every year or two demanding tribute or destruction, and the newcomers' salvaged metal and stranger skills turn out to be exactly what the locals need to make a stand. Reaching safety, though, means an arduous journey by wind-driven ice-raft first. The opening novel of Alan Dean Foster's Icerigger trilogy.