Old New Worlds intertwines the immigrant stories of the author and her great-great grandmother. Sarah Barker and her new husband sail from England in 1815 to minister to the indigenous Khoihoi in South Africa's Eastern Cape. In the midst of conflict, illness, and natural disasters, Sarah bears sixteen children. Two hundred years later, Judith leaves post apartheid South Africa with her new American husband to immigrate to the United States. She is drawn to Sarah's immigrant story in the context of her own experience, and she sets out to try and trace her. In the process, she finds a soul mate.