China is one of the most ethnically heterogenous countries in the world. But the magnitude of its population still allows for over 100 million of its citizens to be classified as ethnic minorities. There are 56 official ethnic groups (minzu), including the majority group of over 1 billion Han Chinese. Members of the 55 minority groups may qualify for affirmative action preferences in high school and university admission. The one child policy is also relaxed to allow two or rarely three children in some minority areas. Which ethnic group you belong to is sometimes a matter of choice, I have a friend who is half Bai and half Han. His sister chose to be classified as Bai, he chose Han.
More than 100 million (8%) Chinese citizens (about the population of Mexico) belong to 55 state-designated ethnic minority groups. Centuries of isolation and autonomy have made many of them linguistically and culturally distinct from the majority Han. Most minorities live in southern China,Tibet, the western province of Xinjiang, or near the borders of Burma, Laos,Vietnam, India, Russia, Mongolia, North Korea and the former Soviet republics of Kazakhstan, Kyrgyzstan and Tajikistan. Minorities make up the bulk of the population in 60% of China’s territory, namely in Tibet and Xinjiang; areas containing important sources of timber, water and petroleum.