Volume four of the Selected Letters of Robert Penn Warren covers a crucial time of personal and professional rejuvenation in Warren's life. During the fifteen-year period spanned by this correspondence, he completed Brother to Dragons; Segregation: The Inner Conflict in the South; and Who Speaks for the Negro? As these titles suggest, these years were marked by Warren's immersion in American history and his maturing interest in race relations. They also saw his return to lyric poetry, after a ten-year hiatus, with the publication of the Pulitzer Prize--winning collection Promises. Along...