The Buddha in the Atttic by Julie Otsuka.
So happy that I've finally figured out how to borrow library books for my Kindle. This one first came to my attention when I heard the author interviewed on the radio. It's about Japanese 'picture brides' who came as a group to America to marry the men who sent for them. It follows the difficulties of their lives in a new country, and their move to internment camps in World War II.