Today, strange as it may seem, Muslims are the most widely distributed of all China's fifty-five formally recognised ethnic minorities. They live in all of China's provinces and have erected mosques in all its major cities. Muslims are China's second largest religious group; they have far outnumbered Christians in China and former Chinese Jews were even sometimes regarded as a sect of Islam.

Muslims were at one time a privileged class above the native Han Chinese and, when later subjected to duress under Chinese authority, they rebelled in nearly three centuries of protest that caused the loss of millions of lives. Muslims in China have dominated important occupational specialisations, played important military roles, and been a source of concern to all Chinese regimes including the present.

Muslims are found all over China, reflecting the variety of paths by which their forbears reached the celestial kingdom: via trade routes to the south and east and via invasion routes from the north and the west. There are Muslim colonies in most of the major cities, including the large eastern metropoles of Beijing, Shanghai, and Tianjin. Rural Hainan Island, far to the southeast, has a sizeable Muslim community, as does Tibet's Lhasa, the holy city of Lamaist Buddhism. There are so-called Panthay Muslims in China's northwest, where their influence, and even their numbers, were predominant for many centuries. This is particularly true of the four northwestern "Muslim belt" provinces of Xinjiang, Qinghai, Gansu, and Ningxia.

Ten ethnic groups of some size are virtually wholly Muslim in faith: the Turkic Muslims (Uighur, Kazak, Kyrgyz, Salar, Uzbek and Tatar); the Persian Muslim Tajik of Xinjiang; the Mongolian Muslims (Dongxiang and Bonan); and the Hui, who have their largest concentrations in Qinghai, Gansu, and Ningxia. So-called "scattered Hui" are also found in most Chinese cities. The Miao of South China, the same group known in Indochina as Meo, have had a substantial number of converts to Islam.

As well as being geographically dispersed, China's Muslims are found in a variety of professions, "a tendency...to follow the more adventurous of the subsidiary callings, or those which require more hardihood and daring". Such occupations as innkeeper, trader, muleteer, carter, soldier and the like attract many more Muslims, proportionately, than Chinese. Many Muslims, including the Uighur, Hui and Miao, are engaged in sedentary agriculture, while the Kazak and Kyrgyz are nomadic herders. Popular professions for urban Hui are, in addition to trade, the butchering of cattle and ownership of "pure and true" restaurants which conform to Islamic dietary strictures. These last two callings enjoy a reputation for high sanitary standards among non-Muslim Chinese, as well, and are well patronised by them. All of China's Muslims are reputed to be excellent soldiers.

Each Islamic group (save the Chinese-speaking Hui), uses its own language. Before 1949 those who were literate - an estimated 20 per cent of population, though most males had had some training in the Qu'ran - read in Arabic. Birthrates, particularly for the Turkic Muslim groups were high, though the Hui birthrate was lower than that of the Han.

The socio-political organisation of Islamic communities in the Muslim belt was cohesive, with whole villages tending to be either Muslim or Han and their inhabitants having little to do with one another. In the urban coastal areas where Muslims were a minority, they tended to cluster together on certain streets, forming Muslim enclaves within the city. The largely Turkic Muslim groups of Xinjiang were more decentralised around local clan and lineage groups, but overlapping ancestral connections provided links, as did their common Muslim faith.

It has been traditionally accepted in Chinese-Muslim historiography that all Muslims in China are Sunni of Hanafi School. Even tentative conclusions which had identified proto-Shi'ite propensities among some currents of New Teaching (Xin Jiao) in China have been contested in various quarters.

Muslim leaders were powerful individuals, able to mobilise large numbers in battle on very short notice. When organised around such a strong leader, different clans and ethnic groups were welded into a formidable fighting force. This was particularly true when the cause was a holy war, which most Muslim grievances quickly escalated into.

The People's Republic of China (PRC) has three major concerns regarding the Muslim population:

• Muslims occupy territory along China's vulnerable international frontiers, especially that with the former USSR;
• The minority tribes - including the Muslims - have a history of uprisings and political unrest;
• The northwestern provinces have great economic value because only about 15% of China's land is arable and therefore the dairy and meat resources of the grasslands could provide much food for an already overpopulated nation.