For forty years from 1837, Presbyterian missionaries Stephen Return Riggs and his wife, Mary, labored among the Wahpetons; a band of the Santee Lakotas (Sioux) in Minnesota. At first intent on studying the Lakota language as a means to evangelism, Riggs eventually came to see in the use of the native tongue an enlargement of the gospel rather than its degradation. With the help of several influential Indians who saw the benefits of communication, the mission published a Lakota grammar and dictionary in 1852 and later in the decade a Lakota hymnbook and selections from the New Testament. Over the years a core of interested Wahpetons kept up the missionaries' hopes for widespread conversions despite indifference and opposition from many others. The plight and the struggle of the native Christian was poignantly illustrated by Simon Anawangmane, the first full-blooded Lakota man to declare himself a Christian...