To commemorate the recent sesquicentennial of Charles Sumner’s death, this installment of “Civil War Treasures” features transcriptions of four of his letters held in the LSU Libraries Special Collections. Although not the most detailed of missives, they all date from significant periods of his tenure in the Senate: the imbroglio over the passage of the Kansas-Nebraska Act, Sumner’s assault at the hands of Preston Brooks, and his evaluation of an ever-worsening situation during the secession crisis in the winter of 1861.