1. Joshua L. Chamberlain: The Life in Letters of a Great Leader of the American Civil War by Thomas Desjardin (Osprey Publishing, 2012).
From publisher: "This new volume brings to public light 300 never-before-seen letters from Chamberlain's personal correspondence, which comprises letters sent by or to Chamberlain from his college years in 1852 to his death in 1914. The first 100 letters shed light on Chamberlain's formative years and his courtship with Fannie Adams, which has been the source of much speculation by scholars. The final 200 letters reveal insights into Chamberlain the Union commander and the aftermath of the war."
2. The Union Forever: Lincoln, Grant, and the Civil War by John Y. Simon, ed. by Glenn LaFantasie (UP of KY, 2012).
This is a compilation of previously published Simon essays on a variety of Grant and Lincoln subjects, in both isolation and intersection.