Ulysses S. Grant did more than any other single Union general to secure the North's victory in the Civil War, but he did not achieve that victory alone. Grant's ability to inspire and cultivate the talents of the officers serving under him was a key factor in his remarkable military success. Steven Woodworth and his fellow authors provide ample evidence for that in this first of a two-volume reassessment of Grant's officer corps from Cairo to Appomattox. Covering the war's western theater through July 1863, Woodworth et. al. highlight the character and accomplishments of these men and show how their individual relationships with Grant helped pave the way to Union victory. They demonstrate how each officer's service contributed to Grant's success and development as a general, how interaction with Grant affected each officer's career, and how the relationship ultimately contributed to the course of battle and the war's final outcome. These portraits include the most important of Grant's lieutenants as well as some who are representative of various officer types. Here are William T. Sherman and Grant's other trusted commanders from the Army of the Tennessee, revered mentor Charles F. Smith, and difficult subordinate William S. Rosecrans. Here too are such citizen soldiers as Lew "Ben Hur" Wallace and Peter Osterhaus, de facto intelligence chief Grenville Dodge, and naval officers Andrew Foote and David Dixon Porter, whose relationships with Grant proved crucial to the war effort.