The protesters, which also included Japanese activists, protested in front of the Chinese embassy in the city.

The protests come in response to new rules in the Inner Mongolia region that will require three subjects — language and literature, politics and history — to be taught in Mandarin, the language of China’s Han majority and the official national language, effective in September, reports The Washington Post.

Although authorities say the rules are being gradually rolled out to cover only those three subjects, activists say they presage a broader effort to roll back the use of Mongolian, mirroring campaigns underway in ethnic Tibetan and Uighur parts of the country that have left a younger generation of minorities monolingual and unmoored from their cultural roots, reports the American newspaper.

In the early 1980s, China’s relatively relaxed policies and the national constitution emphasized that minority languages must be “valued and respected.” In Inner Mongolia today, Mongolian remains an official language, alongside Chinese, the newspaper reported.

Yet over the last five years, China’s government has veered sharply toward the assimilative approach under the hard-line leadership of Xi Jinping, who has promoted classical Chinese culture and fanned Han nationalism while restricting minority languages and religious practices among Tibetans and Uighurs — the latter of which are forcibly detained and reeducated in sweeping numbers.

Educators who promote minority languages have sometimes been charged with separatism and punished severely, the newspaper reported.