Historical race concepts
People from different places tend to look different. Some scientists in the 18th century decided to classify them into a limited number of variants or races. Some spoke of three races of mankind: The Caucasian race living in Europe, North Africa and West Asia, the Mongoloid race living in East Asia, Australia, and the Americas, and the Negroid race living in Africa south of the Sahara. Others preferred two, with the others arising from mixtures, and some chose four, five, or other numbers of races.