Like many other alternate histories it's a story of a world where Europe never became a dominant world power. Europe has been beaten down by centuries of Mongol domination, leaving it shattered and broken. England is a failing feudal state, selling its people as slaves to pay for its incessent wars. Here, like Kim Stanley Robinson's Years Of Rice And Salt, the Americas are divided between the Moors and the Chinese.
Finn, an Irish bard, has crossed the High King by sleeping with his daughter. He needs to leave the Ireland, fast, and stows away on a ship heading for Tangiers - the crossroads of the world. Things never quite go to plan, and he finds himself sold into slavery and sent off to the Americas. It's a journey that will take him from all but certain death the land of the Mexica to the high plains, via trading posts, camels and dancing girls. He'll meet kite-gliding ninja, Russian invaders and the Chinese secret service before he finally arrives in the fabled city of Fusang.
Sanders' story is a simple one: the journey to a promised land, in this case the Chinese city of Fusang (situated where we'd find Sand Francisco). There's much to criticise about the construction of his counter-factual world, but we can forgive the innacuracies and the fancies - we just need to remember that it's not there to be the heart of the story, it's just another piece of background. What's more important is Finn's journey. And this is pure romp - light hearted and thrilling, with plenty of derring do and action. There are similarites with the Flashman novels of George Macdonald Frasier - the unreliable narrator (in more ways that one), and the role of the crook and conman in larger events.
A fun, light read. Enjoyable.