Disney is well aware that Star Wars hasn't built the same box office traction in China, so they've put in a lot of effort over the years trying to ramp up recognition. This kicked off in the months leading up to the release of 2015's The Force Awakens, when the company placed 500 stormtroopers on the Great Wall and hired pop star Lu Han to be an "official ambassador" for the movie.
Disney's efforts ahead of The Force Awakens also included making all six of the previous Star Wars films available for streaming via the Chinese company Tencent. Their efforts paid off, at least in part, for The Force Awakens, which pulled in a solid $52.5 million. However, as ComScore senior media analyst Paul Dergarabedian points out, that movie had the benefit of "a decades-long build-up" to its release.
For The Last Jedi, Disney tried once again to drum up the buzz they got for The Force Awakens. This included a significant number of billboards and mobile ads, as well as a premiere at the Shanghai Disney Resort featuring the film's biggest stars. However, Dergarabedian believes that it may have been too little, too late. "To elevate the brand in China," he said, "it may be a matter of consistency more than anything else."
It's worth noting that the standalone Rogue One: A Star Wars Story also earned a release in China, bringing in $32.4 million in its opening weekend—more than The Last Jedi. That film, however, had the benefit of two local stars, Donnie Yen and Jiang Wen, who lured audiences in.