In Xinjiang, a region of deserts and mountains that makes up one-sixth of China’s landmass, more than 43 percent of the population is Uighur and more than 40 percent is Han, according to a 2000 census, the most recent data available. The Han population in the region has surged since the Communist takeover of China in 1949, fueling anxiety among Uighurs. Kazakhs make up 8 percent of the population, and the rest are Hui, Kirghiz and Mongols, among others.

At a high-level policy meeting in Beijing in May, Communist Party leaders discussed how to better assimilate Uighurs into Chinese society and tamp down violence in Xinjiang.

Mr. Xi, the Chinese president and party leader, said at the meeting that more Uighurs should be moved to Han-dominated parts of China for education and employment. He said the party and the state should establish “correct views about the motherland and the nation” among all of China’s ethnic groups, so that people of every background will recognize the “great motherland” and “the socialist path with Chinese characteristics.”

The promotion of Han-Uighur marriages is one of the policies to emerge from that meeting, said James Leibold, a scholar of China’s ethnic policies at La Trobe University in Melbourne, Australia. He noted that the most recent data available showed that only 1 percent of Uighurs were in an interethnic family, compared with nearly 8 percent of Tibetans. The average among all ethnicities was more than 3 percent, but the Han also had a low rate, 1.5 percent.

Communist officials have long promoted popular tales of mixed marriages to paper over ethnic conflicts, including the story of the Fragrant Concubine, a Uighur woman who was brought in the 18th century to the imperial court in Beijing to be the consort of the Qianlong Emperor, an ethnic Manchu.

Many Han talk of how the Manchus from the northeastern forests, who conquered China to establish the Qing dynasty, eventually adopted Han customs and intermarried, citing this as an example of how Han Chinese civilization inevitably absorbs and assimilates other ethnicities.

In June, Tibet Daily published a report saying that Chen Qianguo, the party chief of the Tibet Autonomous Region, had met with 19 interethnic couples and heard stories of happy marriages. Mr. Chen said “favorable policies” for interethnic couples had resulted in an increase to 4,795 interethnic marriages in 2013 from 666 in 2008.

Promoting Han-Uighur unions is one of several new policies being pursued by local governments in Xinjiang. Last month, Karamay City temporarily banned people with long beards and Muslim dress from boarding buses. In April, Shayar County began offering rewards to anyone who reported on people believed to be growing long beards or visiting a mosque while under age 18, among other things.