This article focuses on the presence of companion animals in Union army camps during the US Civil War. It argues that soldiers turned to animals of all kinds (including cats, dogs, mice, and pigs, along with less common species), despite official sanction against such practices, to ameliorate boredom and to distract themselves from the horror at hand. Most importantly, pets helped the soldiers reconnect with their humanity in the midst of the necessarily dehumanizing act of waging war. The study draws principally on the letters and journals of Federal soldiers, along with sketches and photographs, to demonstrate not only animals’ ubiquity of in military camps but also their importance to the men at war.