Throughout the American Civil War, northern photographers, many of whom were officially attached to the Union army, generated more than seven thousand images of Union commanders and ordinary soldiers, faraway landscapes, and scenes of unprecedented death and destruction. In doing so, they aimed to create a supremely objective, visual history of the war. Because these photographs have so thoroughly influenced how generations of Americans have understood and remembered the Civil War, it is imperative to examine how northern photographers, Union military and political officials, and the American public conceived of the pictures’ contemporary enduring historical significance. In particular, this paper focuses upon the work of Mathew Brady, the first Civil War photographer to travel to the front lines and whose collection of Civil War negatives was purchased by Congress in 1875, and of Alexander Gardner, Brady’s employee-turned-competitor, whose 1866 Photographic Sketch Book of the War was the first published book of American photographs. These bodies of work have been analyzed at length by historians of American photography, but they have not received adequate attention from political and intellectual historians of the Civil War and Reconstruction periods. Indeed, Americans’ estimation of the relationship between photography and history serves to shed light on how they absorbed the war’s events and how they perceived the role that history played in their own lives—an especially essential endeavor given the degree to which both Union and Confederate officials were concerned, even during the war itself, with how their respective causes would be remembered. While Brady, Gardner, and their compatriots asserted that their photographs held a unique claim to objectivity, and thus to historical significance, they were thoroughly implicated in the Union political project. Moreover, photography’s technical limitations ensured that it could not capture in real time what nineteenth-century conceptions of history deemed most important—namely, epic scenes of battle. By focusing instead upon ordinary soldiers performing mundane activities or upon the corpses of the dead, Civil War photographers fundamentally challenged prevailing notions of what and who constituted history’s rightful subjects.