Actress Gina Carano has sued Disney and Lucasfilm after she was sacked in 2021 over a social media post in which she compared being a Republican to being a Jew during the Holocaust.
The lawsuit is being funded by Elon Musk, who made an open call on his platform X for others to join the suit.
Ms Carano is seeking $75,000 (£60,000) in damages. She is also asking the court to force Lucasfilm to recast her.
Representatives for the defendants were not immediately available for comment.
Ms Carano, 41, a former MMA fighter, portrayed Cara Dune in the first two seasons of the Disney+ show The Mandalorian.
During that time, she frequently tangled online with left-wingers.
But critics demanded she be fired after she shared a post on her Instagram account in February 2021 equating the persecution of Jews by the Nazis to the political climate Republicans face today.
"Because history is edited, most people today don't realize that to get to the point where Nazi soldiers could easily round up thousands of Jews, the government first made their own neighbors hate them simply for being Jews," the post read.
"How is that any different from hating someone for their political views."
That same day, Ms Carano was dropped by Lucasfilm, the production company behind the show, as well as UTA, the talent agency that had represented her for nearly two years.
In a statement at the time, a Lucasfilm spokesperson said "her social media posts denigrating people based on their cultural and religious identities are abhorrent and unacceptable".
UTA is not named in Tuesday's court filing, which alleges that the Walt Disney Company was at fault for the agency dropping her.
The 59-page civil suit, filed in California federal court, lays out allegations of wrongful termination and retaliation in a narrative laden with Star Wars references.
"A short time ago in a galaxy not so far away, Defendants made it clear that only one orthodoxy in thought, speech, or action was acceptable in their empire, and that those who dared to question or failed to fully comply would not be tolerated," the complaint begins.
Ms Carano claims she was fired "because she dared voice her own opinions... and stood up to the online bully mob who demanded her compliance with their extreme progressive ideology".
The lawsuit alleges that the actress was treated differently from two male co-stars, who wrote or shared posts online maligning Republicans as Nazis but faced no penalty.
In a lengthy statement on X, Ms Carano said she had been subjected to "a bullying smear campaign aimed at silencing, destroying & making an example out of me".
"Artists do not sign away our rights as American citizens when we enter into employment," she added, thanking Mr Musk and those who have supported her.
The billionaire shared her statement, writing: "Please let us know if you would like to join the lawsuit against Disney."
Mr Musk has previously vowed to financially support those facing discrimination for their posts on X.
In a statement, a spokesperson for his company said it was "proud" to back Ms Carano's lawsuit as part of its commitment to free speech.