It marked the first time an openly gay superhero would lead their own television series. The casting was praised and Rose — who identifies as genderfluid — initially thanked fans.
Many people welcomed Rose and celebrated the historic casting.
However, there were also those who criticized the choice — some felt Rose was an obvious, maybe lazy choice by the show's creators, or simply not a good enough actor.
Others accused the CW of "goywashing" the character's Jewish identity. The hashtags #RecastBatwoman and #KeepKateJewish began to circulate on Twitter.
"They cast a non-Jewish woman," she said. "I personally think it's about time Hollywood truly becomes inclusive and equal of minority groups and of course proper representation. Batwoman is one of the great places to start on that."
Actor Ashley Platz became a focal point of these campaigns. After her audition tape for the role of Kate Kane was leaked, people began to say that she deserved the part.
A petition was even started by one fan, Tantoun, a 30-year-old from Qatar.
She also said that those campaigning for a Jewish Batwoman had been, in her opinion, peaceful and that she had received online abuse from Rose supporters via her Curious Cat account.
Last week, Platz tweeted a statement about the campaign, thanking fans, but giving her support to Rose.
Rose and Batwoman fans were also criticized by people who feel Batwoman is a "social justice warrior" character.
Over the weekend, Rose announced she would be quitting Twitter, and specifically referenced criticism of her sexuality.
"Where on earth did 'Ruby is not a lesbian therefore she can’t be batwoman' come from – has to be the funniest most ridiculous thing I’ve ever read," she said in a final tweet. "I came out at 12? And have for the past 5 years had to deal with 'she’s too gay' how do y’all flip it like that? I didn’t change."