Assorted chiles that are popular in U.S. kitchens (photo courtesy Melissa’s).
 Cayenne chiles (photo courtesy Good Eggs).
Wild chiles have been a part of the diet in the Americas since about 7500 B.C.E.
While the first chile may have been domesticated in Bolivia, the oldest known traces of have been found in bowls in Ecuador, dating back 6,100 years*.
Chiles were carried to different parts of Latin America, where soil, climate and cross breeding created many different species. Today there are six species of chiles in the genus Capsicum.
But how did we get so many different spellings for the chile?
Chilli: The original word in Nahuatl, the language of the Aztecs, is “chilli,” the spelling that is used in the U.K. and its former colonies.
Chile is the spelling used by the Spanish, the first Europeans to taste them, who adapted the spoken word to their spelling conventions. They first brought chiles to Europe in the mid-1500s.
Chile is used in the U.S. to describe any hot Capsicum.
Bell pepper: The mildest member of the genus became known as bell pepper in the U.S. (because of its shape), but is called capsicum in the U.K.
Chile pepper is a misnomer that has stuck, unfortunately, thanks to Christopher Columbus. Upon first tasting chiles in the Caribbean, he equated them to the only other spicy hot food he knew: black pepper, which had been available in Europe since Roman times.
Black pepper (Piper nigrum) and chiles (Capsicum) are not related in any way. See the details below.
Chili powder, a mixture of ground chiles and other ingredients cumin, garlic powder, onion powder, oregano), is a spelling common among American spice manufacturers.
And by the way:
Chiles are a fruit, not a vegetable. Here’s the difference between fruits and vegetables.
SO WHAT SHOULD YOU CALL THEM?
But Columbus’ name stuck, but it isn’t correct. Our suggestion is to simply call hot chiles—ancho, jalapeño, habanero, serrano, etc.—chiles.
For the fruits: chile. (In New Mexico, a big chile state, this official spelling was entered into the 1983 Congressional Record [source]).
For the ground spice and the Tex-Mex dish it’s used in: chili.
As for chilie and chilly: Don’t even go there!
If you live in the U.S. (we can’t address other countries):
The History Of Chiles
The Scoville Scale, classifying chiles by hotness
The Different Types Of Chiles
*Science magazine, February 16, 2007.
†Taxonomy includes Kingdom, Subkingdom, Infrakingdom, Superdivision, Division, Subdivision, Class, Superorder, Order, Family, Genus, Species. The simplified list is Kingdom, Division, Class, Order, Family, Genus, Species. Black pepper (Piper nigrum genus and species) and chiles (Capsicum genus, 6 different species), are not related at all, although both are in the plant kingdom.
IS BLACK PEPPER RELATED TO CHILES IN ANY WAY? NO!
Their only relationship is that they are both members of the plant family in the official taxonomy.
Taxonomy is the branch of science concerned with classification of organisms plants and animals.
Kingdom Plantae Plants
Infrakingdom Streptophyta – land plants
Division Tracheophyta – vascular plants, tracheophytes
Subdivision Spermatophytina spermatophytes, seed plants
Family Piperaceae – peppers
Genus Piper L. – pepper
Species Piper nigrum L. – black pepper
Kingdom Plantae – Plants
Subkingdom Tracheobionta – Vascular plants
Superdivision Spermatophyta – Seed plants
Division Magnoliophyta – Flowering plants
Class Magnoliopsida – Dicotyledons
Family Solanaceae – Potato family
Species Capsicum annuum
Species Capsicum baccatum
Species Capsicum chinense
Species Capsicum frutescens
Species Capsicum pubescens
Species Capsicum praetermissum
 Jalapenos, habaneros and a glimpse of red bell peppers. The pink peppercorns shown in the photo are not related to Piper nigrum, nor to Capsicum. They’re berries from the Baies Rose Plant (Genus and species Schinus molle, Family Anacardiaceae), a small mastic tree related to the rose bush, from the French Island of Reunion in the Indian Ocean. Green peppercorns are immature black Piper nigrum peppercorns, picked while unripe.
 Bell peppers, the non-spicy chile.
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