Heart of a Samurai

Heart of a Samurai by Margi Preus

There are events and characters in history that seem so extreme that they could / should be fiction. Heart of a Samurai is based on the true life events of a young japanese boy - Manjiro. I gained a greater understanding of this period of history in Japan and didn't feel like I was having a history lesson.

From the inside cover:
In 1841, fourteen-year-old Manjiro and his four friends find themselves stranded on a deserted island after a storm at sea. Beyond the island is the unknown, filled with monsters, demons, and barbarians. Or so they've been told. They know they cannot return to their homes in Japan - the country's borders are closed both to foreigners and to citizens who have strayed. No one may enter, under penalty of imprisonment and even death!
One day an American ship passes near the island and takes the castaways aboard. Manjiro's curiosity overcomes his fear of the barbarians. He joins in the work of the whaling vessel, eager to learn everything he can about this new culture. Over the next ten years, Manjiro travels the high seas, visiting places he never dreamed existed, including America. It is a time filled with new experiences and adventure, as well as friendship and treachery. Manjiro sustains himself on a dream of returning home and somehow - though he knows it is impossible for a simple fisherman - becoming a samurai.
Will he ever be able to go back to his native land? And if he does, will he be welcomed or condemned?

If you prefer non-fiction here's another option for you.
Shipwrecked! the true adventures of a Japanese boy / by Rhoda Blumberg