Volume IV of this series brings to a close nearly ten years of research and publication of Sam Houston's correspondence by Madge Thornall Roberts and the University of North Texas Press. As befitting a final volume in this series, it includes a comprehensive index of all four volumes. Volume IV continues with letters from 1852 showing Houston's concern over the approaching Civil War and his hopeless struggle to prevent it. His letters during the Civil War prior to his death reveal his feelings on military strategy and his pride and mixed emotions as his eldest son joins the Confederate Army.

Letters up until the time of Margaret's death are also included as they add insight to family life during the Civil War and early Reconstruction. In addition, Volume IV includes letters from earlier periods uncovered after the publication of the previous volumes. These letters from his sisters, brother, and cousins are particularly interesting because they show concern over Houston's resignation as governor of Tennessee and (later) the gravity of his San Jacinto wound. They also reveal the feelings of local Tennessee friends on the events in Texas.