It was a warm evening in California when four men sat by a fire. The German spoke first, recalling how he had come in the 1840s during the Gold Rush, hoping to make a quick fortune like thousands of other Europeans. "I found some gold," he admitted, "but most of us returned empty-handed."

The Chinese labourer nodded wearily. He had been recruited to build the railway lines across the continent, which was completed by 1870. "We provided cheap labour," he said, "but now the government wants to ban Chinese immigrants because they fear depending on non-whites."

The former African slave listened silently. He knew what it meant to work without freedom. He had heard that some natives were employed in farms under conditions so harsh that it was little different from slavery. The Hopi man understood suffering too. He spoke of the stone tablets that foretold the coming of strangers. "When the Spanish Conquistadores came covered in armour like turtles, our people welcomed them, but they dropped trinkets into our hands instead of friendship," he said. "Word spread throughout North America that human beings were going to suffer because some had forgotten the sacredness of all things."

The four men sat together, each carrying the weight of a changing land where anthropologists now studied them as 'primitive' communities expected to die out.