This article addresses "race" as a social practice, a construction, and as an idea that has been developed through the power of discourse. This category, rather than a biological reality, is an intellectual and social construction which has had a variety of meanings attributed to it through history. The concept of "race," however, has preserved its functionality: to differentiate, segregate, and distort otherness. In this way, it has racialized social relations through biological determinism. To substantiate this hypothesis, the article undertakes a historical analysisto demonstrate the dynamics and variability of the racial imaginary. It sketches the outline of a history of race that includes the Spanish idea of the "Purity of Blood" (16-17th centuries), the legitimizing discourses of the French nobility (17-18th centuries), the ambivalence of the Enlightenment, as well as 19th century scientific racism as a prelude of the Holocaust or Shoah. The article concludes with some reflections derived from genetics as additional proof of the fictional nature of the concept of "race."