Chili peppers have been a part of the human diet in the Americas since at least 7500 BC. There is archaeological evidence at sites located in southwestern Ecuador that chili peppers were domesticated more than 6000 years ago,and is one of the first cultivated crops in the Americas that is self-pollinating.
Chili peppers were domesticated at least in different parts of South and Central America.
Christopher Columbus was one of the first Europeans to encounter them (in the Caribbean), and called them "peppers" because of their similarity in taste with the Old World black peppers of the Piper genus.
Chilies were cultivated around the globe after Columbus. Diego lvarez Chanca, a physician on Columbus' second voyage to the West Indies in 1493, brought the first chili peppers to Spain, and first wrote about their medicinal effects in 1494.
From Mexico, at the time the Spanish colony that controlled commerce with Asia, chili peppers spread rapidly into the Philippines and then to India, China, Korea and Japan. They were incorporated into the local cuisines.
An alternate sequence for chili peppers' spread has the Portuguese getting the pepper from Spain, and thence to India, as described by Lizzie Collingham in her book Curry. Collingham states in her book that the chili pepper figures heavily in the cuisine of the Goan region of India, which was the site of a Portuguese colony (e.g. vindaloo, an Indian interpretation of a Portuguese dish). Collingham also describes the journey of chili peppers from India, through Central Asia and Turkey, to Hungary, where it became the national spice in the form of paprika.
There are speculations about pre-Columbian chili peppers in Europe. In an archaeological dig in the block of St. Botulf in Lund, archaeologists found a Capsicum frutescens in a layer dating to the 13th century. Hjelmqvist says that Capsicum was described by the Greek Theophrastus (370-286 BC). He mentions other ancient sources. The Roman poet Martialis (around the 1st century) described "Piper crudum" (raw pepper) to be long and containing seeds. The description of the plants does not fit black pepper (Piper nigrum) but does fit that of long pepper. Another pre-Columbian European reference is found in the writings of the Jewish scholar Rashi (1040-1105), who lived in Troyes, France. In his commentary to the Babylonian Talmud Tractate Avodah Zarah 66a under the words "seasonings of two or three different names", he cites white pepper, black pepper, and long pepper.