In 1838, Ansten Knutson Nattestad returned to Norway from America. He caused a great sensation. He brought back the manuscript of Ole Rynning, of Tinn, that when it was published became the first of what became known as the "America Books". Significant in this book, published twenty two years before the American Civil War, speaking about slavery, Ole Rynning wrote "there will probably soon come either a separation between the northern and southern states or bloody civil conflicts".