timelets

“In the 1400s, people began to use a new word to define a group of animals that shared the same blood: a race. A Spanish manual from around 1430 offered breeders tips for providing a “good race” of horse.

A priest named Alfonso Martínez de Toledo declared in 1438 that it’s easy to tell the difference between men belonging to good and bad races.

In the late 1400s, Jews in Spain found themselves defined as a race of their own.

In 1449 the Spanish city of Toledo began turning this hostility into law, decreeing that even a trace of Jewish blood disqualified a subject from holding office or marrying a true Christian.
The ban spread across Spain, expanding its scope along the way. Jewish blood now barred people from getting university degrees, inheriting estates, or even entering some parts of the country. In order to define Jews as a separate race, the majority of Spain had to define itself as a race of its own. Noble families now claimed that their genealogies extended back to the Visigoths. They boasted of the cleanliness of their blood, known as limpieza de sangre. They extolled the pale skin of Old Christians, which revealed the sangre azul—blue blood—coursing in the vessels beneath.

Carl Zimmer. “She Has Her Mother's Laugh.”

Now, I see the point in considering race to be a purely social construct to objectify "good vs bad" people.
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