Nancy Horan is an American writer of historical fiction, best known for Loving Frank, a novel about Mamah Borthwick and her relationship with architect Frank Lloyd Wright. Her other book, Under the Wide and Starry Sky, follows Robert Louis Stevenson and his wife. Loving Frank was awarded the 2009 James Fenimore Cooper Prize for Best Historical Fiction by the Society of American Historians. Earlier, she taught middle school English and worked as a freelance journalist, and she now lives on an island in Puget Sound with her husband.