How do the characteristics of military leaders relate to battlefield outcomes? To answer this question, we employ original battle-level data and biographical information on hundreds of commanders in more than 250 battles in the American Civil War. We examine the relationship between two common measures of battlefield success (victory and casualties) and two latent features of commanders—competence and loyalty—that have long been seen as important in the broader study of executive appointments. We find that competent commanders are associated with more successful battlefield outcomes, as are more loyal Confederate commanders. More broadly, our analysis suggests that focusing on the relationship between military appointments and battlefield outcomes—with the latter’s relatively clear definition of “success”—allows for direct examination of the relationship between appointee traits and organizational performance. As such, our results have implications for the study of conflict as well as bureaucratic politics.