Blood has long been a signifier as well as a substance. As such, it discloses historical changes in the way language conceptualizes life – in particular, the shared life that is human kinship. A scene from Joel Chandler Harris’s novel Gabriel Tolliver (1902) captures with vivid precision one of the postbellum transformations of the trope of blood. Set in the troubled era of US Reconstruction, the scene begins when white leaders of a local Union League meet with Black parishioners in a church in Georgia in hopes of building a new political alliance. But the meeting is soon interrupted by thirteen white-robed riders on horseback, a show of force by the local Ku Klux Klan. At first the riders circle the church in a menacing silence. When the terrified Black parishioners finally flee the rustic church, the riders fire pistols and repeatedly chant the word “blood.” In this moment of high drama, “blood” is deployed as a complex speech act, at once a threat of violence (blood as substance) and an assertion of racial identity (blood as signifier).