When Abraham Lincoln issued his final Emancipation Proclamation on January 1, 1863, he not only freed the slaves in the Confederate states but also invited freed slaves and free persons of color to join the U.S. Army as part of the U.S. Colored Troops (USCT), the first systematic, large-scale effort by the U.S. government to arm African Americans to aid in the nation's defense. By the end of the war in 1865, nearly 180,000 black soldiers had fought for the Union. Lincoln's role in the arming of African Americans remains a central but unfortunately obscure part of one of the most compelling periods in American history.  In Lincoln and the U.S. Colored Troops John David Smith offers a concise, enlightening exploration of the development of Lincoln's military emancipation project, its implementation, and the recruitment and deployment of black troops.   Though scholars have written much on emancipation and the USCT, Smith's work frames the evolution of Lincoln's ideas on emancipation and arming blacks within congressional actions, explaining how, when, and why the president seemed to be so halting in his progression to military emancipation. After tracing Lincoln's evolution from opposing to supporting emancipation as a necessary war measure and to championing the recruitment of black troops for the Union Army, Smith details the creation, mobilization, and diverse military service of the USCT. He assesses the hardships under which the men of the USCT served, including the multiple forms of discrimination from so-called friends and foes alike, and examines the broad meaning of Lincoln's military emancipation project and its place in African American historical memory.