The United States and Canada are home to a rich diversity of ethnic and cultural groups. Various observers have described this diversity as a “melting pot” or a “tossed salad.” It might better be described as a cultural mosaic, one with remarkably vivid geographical elements. Shaping this mosaic has been an ongoing series of migrations and settlements, cultural interactions and exchanges, adaptations and innovations, and diffusions. Over time, North America’s many ethnic groups have also made visible and lasting impressions on the landscape.