For hundreds of thousands of immigrants, coming to Massachusetts has meant exchanging one community for another in multiple ways that are often overlooked. Whether home was originally an Irish tenant farm or the slave quarters of a Southern plantation or an Eastern European ghetto, whether its mention evoked warm memories or nightmares, immigration has required adopting a new identity consonant with new circumstances. Men who considered themselves Milanese moved to Boston's North End and became Italian Americans; women who identified themselves with County Cork turned into Irish Americans...