By Chun Han Wong

HONG KONG -- Walt Disney Co.'s $200 million live-action remake of "Mulan" is taking fire from human-rights activists over the filmmakers' cooperation with authorities in China's Xinjiang region, where officials have been accused of committing rights abuses against millions of members of ethnic Muslim minority groups.

The movie's credits offer "special thanks" to a number of Chinese Communist Party and government agencies, including eight in Xinjiang, a mountainous frontier abutting Central Asia that about 12 million Turkic-speaking Muslim Uighurs regard as their homeland.

Grant Major, the Oscar-winning production designer who worked on the film, said a small portion of the shooting took place in Xinjiang. Film shoots anywhere in China require permission from local authorities.

Separatist sentiment has long simmered in Xinjiang, where resistance to Communist Party rule has at times flared into deadly attacks against symbols of Beijing's authority and the country's Han Chinese majority.

In recent years, Chinese leader Xi Jinping has sought to crush this movement with a high-intensity campaign that some China policy researchers and rights activists estimate to have put more than a million Uighurs and other Muslims through political-indoctrination programs in mass-detention camps, while subjecting many more to surveillance and assimilation efforts.

Based on an ancient Chinese legend about a woman who disguises herself as a man and goes to war in place of her aging father, Disney's "Mulan" remake features scenes depicting a stretch of the ancient Silk Road that ran through what the film describes as northwest China.

Human rights watchdogs, exiled Uighur activists and foreign academics have criticized Disney over the film's connection to Xinjiang, as has U.S. Sen. Josh Hawley (R., Mo.) on Twitter.

"Mulan is a patriot but she shouldn't be placed in Xinjiang, because patriotism has been forbidden in Xinjiang," where Uighurs have been persecuted for showing love for their homeland, said Abduweli Ayup, a Norway-based Uighur linguist and rights activist, who has joined calls for a boycott of the film. "In China, patriotism is loving the Chinese Communist Party."

Making a "Mulan" that appeals to China fits into Disney's larger mission of courting Chinese consumers, drawing them to its stores and theme parks in Shanghai and Hong Kong. Disney put months of research into "Mulan" and shared the script with Chinese authorities to ensure it would play in Chinese theaters. It is scheduled to debut there Friday.

Disney Chief Executive Bob Chapek told Wall Street analysts last month that the company hoped the film, which premiered online for audiences in the U.S. this past weekend, would stimulate users to sign up for the company's Disney+ streaming service.

It couldn't be determined how Disney or the "Mulan" production crew cooperated with authorities in Xinjiang, though some senior crew members previously indicated they had traveled to that region to prepare for the production.

Mr. Major, the production designer, told The Wall Street Journal that he and other members of the production team spent a few days in Xinjiang doing research before a crew returned to film. He said some exterior shots were filmed in Xinjiang due to the region's significance to the history of the ancient Silk Road.

The film's director, Niki Caro, posted on Instagram in September 2017 a photograph of desert landscape taken during what she called a film scouting trip in China, with the location marked as "Asia/Urumqi," a reference to the capital of Xinjiang.

On Tuesday, some Instagram users left angry comments on Ms. Caro's nearly three-year-old post, criticizing what they saw as a whitewashing of alleged rights abuses in Xinjiang. "Unbelievable how either unaware you are or how you just decided to ignore everything in around you because, hey Disney, hey money," one user wrote. "Are you proud?"

Producers had wanted to film a significant portion of "Mulan" in China but ultimately decided to shoot about 90% of the movie in New Zealand, daunted by the logistics of transporting the entire crew large distances among locations, according to people familiar with the matter. The shoot started in August 2018, according to a Disney blog post.

Disney representatives didn't respond to emails and voicemails requesting comment.

Xinjiang's government didn't respond to a faxed request for comment. Chinese officials have repeatedly denied committing any rights abuses in Xinjiang. They have defended their policies there as effective in stopping separatist violence and restoring peace.

"Certain anti-Chinese forces abroad are smearing and attacking China in Xinjiang," Chinese Foreign Ministry spokesman Zhao Lijian said at a routine briefing on Tuesday, in response to questions about Disney's activities in Xinjiang.

Even before its release over the weekend on Disney+, "Mulan" faced controversy related to Mr. Xi's efforts to enforce Communist Party control over China's periphery.

Supporters of Hong Kong's pro-democracy protest movement have called for a boycott of the movie since its lead actress, Liu Yifei, voiced support for the city's police force last year amid allegations that its officers used excessive force against anti-Beijing demonstrators.

More recently, some Hong Kongers have hailed a local pro-democracy activist, Agnes Chow, as the "real Mulan" after she was arrested last month under a new national-security law that Beijing imposed on Hong Kong.

The latest backlash against "Mulan," a remake of Disney's 1998 animated feature of the same name, first flared on social media, where users posted screenshots from the movie's credits that included references to Xinjiang authorities. The filmmakers thanked Xinjiang's Communist Party publicity department as well as the municipal police and tourism authorities in the oasis city of Turpan, among other agencies.

Former detainees and rights activists say authorities in Turpan, the site of an ancient Silk Road settlement, have participated in China's mass-internment program for Uighurs and other Muslims.

During a 2018 visit the city, a Wall Street Journal reporter discovered one internment camp surrounded by 15-foot-high walls topped with razor wire and punctuated with guard towers. According to a list of suspected detention camps in Xinjiang compiled by Canada-based activist Shawn Zhang, Turpan had at least four internment facilities as of 2019.

In interviews, former detainees at such facilities have described being subjected to lengthy interrogations and political classes, which included watching videos about Mr. Xi and singing patriotic songs praising the Communist Party. They said camp officials instructed them not to pray, keep a copy of the Quran or fast during Ramadan.

The Mulan legend hasn't been widely associated with Xinjiang, a fact that led critics to question why Disney decided to work with authorities there.

While multiple versions of the Mulan fable exist in Chinese literature, scholars have traced the story to the Northern Wei dynasty of the fourth to sixth centuries. The oldest existing record of the "Ballad of Mulan" appeared in an 11th century anthology, and it is often interpreted as depicting a conflict fought in an area that today stretches across northern China and Mongolia, between Northern Wei -- ruled by the nomadic Xianbei ethnic group -- and another nomadic group known as the Rouran.

Two mountains mentioned in the poem "were famous battlefields when the Xianbeis and Rourans clashed," including one located in modern-day Mongolia, according to a 2013 paper by two Chinese professors, Xu Mingwu and Tian Chuanmao. Disney's 1998 animated feature appeared to be a highly Americanized version of the ballad, they wrote.

The Chinese government cautioned the production from focusing on any particular portion of Chinese history or dynasty, according to Mr. Major and other people familiar with the matter.

--R.T. Watson and Micah Maidenburg contributed to this article.

Write to Chun Han Wong at chunhan.wong@wsj.com