Since Batman's introduction in Detective Comics #27 in May 1939, his alter ego Bruce Wayne has been depicted as ethnically and culturally white. As public perception of the character has changed over the years, his privilege as a white male in the 1 percent has become a point of criticism. Bruce Wayne is rich enough to dress up as a bat and run around Gotham beating up criminals and get away with it. However, although Bruce is definitely the poster boy for privilege, he’s not conventionally white: He's Jewish.
This wasn’t always a part of his background, but rather was an unintended retcon that came with the introduction of the new Batwoman in 2006. This iteration is Kate Kane, socialite, soldier, and also Bruce’s cousin. They are related through her father, Jacob Kane, the brother of Martha Wayne. Before marrying Thomas Wayne, her maiden name was established as Kane as a nod to Batman co-creator Bob Kane.
While in real life, Bob Kane was Jewish, Martha’s background isn’t well explored in the comics. When developing Kate and her family, the decision was made to make them Jewish. Kate’s heritage is an important part of who she is, and she continues to practice her religion even as she fights crime as Batwoman. Identifying as Jewish is important to her father, Jacob, too -- and it’s this detail that, by extension, makes Batman Jewish.
Halacha dictates that being a member of the Jewish people is traced matrilineally. Because Jacob’s mother was Jewish, so was he. Kate’s mother Gabi was Jewish, making Kate, and any hypothetical children she were to have, Jewish as well. Unless DC comes out and says Jacob converted, or is only a half-brother, this would make the entire Kane family Jewish. That includes Martha Wayne. So, according to tradition, if Batman’s mother was born Jewish, then so was Bruce. This completely accidental change to his heritage has been ignored so far, and is likely to remain that way.
Jewish identity is a complicated subject, as it is both a religion and ethnicity. Genetically speaking, Bruce is half-Jewish, but at no point in his history has the character practiced the religion of Judaism. It has been explicitly stated that, as a child, Bruce was raised in his father’s faith as an Episcopalian. It’s also been made clear that as an adult, Batman is an affirmed atheist. None of this matters in the eyes of the Jewish faith. Whether he is aware of it or not, Bruce is Jewish. Despite being an atheist, it’s not a part of himself he can opt out of. Other Jewish people will always consider him one, regardless of his opinion.
Even if he isn't Jewish in the eyes of the religion, he would still be Jewish to an anti-Semite. Having any Jewish blood at all is enough to qualify him for their hate.
It’s important to reiterate that, despite all of this new information, Bruce is still effectively white. Batman has not once in his life experienced discrimination based on the circumstances of his birth. Quite the opposite, in fact: Bruce is able to open doors closed to most people simply because he is a rich, white man. It would feel disingenuous and completely ridiculous at this point to have Bruce suddenly embrace this new part of his background and announce he's Jewish, especially since he doesn’t believe in any god at all. Still, there is an opportunity to grow the character in an interesting direction, should DC decide to do so.
So much of Batman’s psyche is constructed around being a Wayne and the responsibilities that entails. He very rarely brings up his relation to the Kanes. Considering Bruce is eternally haunted by the loss of both of his parents, a story involving Martha and her past wouldn’t be much of stretch. A mystery surrounding his mother would be too hard for the world’s greatest detective to ignore.
Beyond providing an opportunity to clarify Bruce’s heritage, it would shine a spotlight on Martha, who -- compared to Thomas -- has been thinly characterized. Bruce loved both his parents and taking the time to elaborate on his relationship with his mother could let fans see a more intimate side of Batman. It could also re-contextualize certain aspects of his personality. The Jewish people have endured thousands of years of persecution. Many great powers in world history have tried to erase them, but their will to survive and retain their culture always prevails. The bulk of Jewish holidays commemorate the numerous times they’ve been subjected to attempted genocide.
Perhaps if he explored his mother’s heritage, Batman would find parallels between their resolve and his. Likewise, Jewish people have known great sorrow and loss, another commonality Bruce shares with his mother’s people. Bruce is constantly wracked by guilt over his actions, and that too is very Jewish of him. No one should expect to see Batman start ordering Alfred to whip up a batch of matzo ball soup or have him start wearing a kippah under his cowl. It just won’t happen; it wouldn’t make any sense. However, Bruce is a pretty insightful guy and if he’s not already aware of his heritage, he would appreciate the significance of knowing where he came from.
Batman will never fully identify as Jewish, nor should he, but he is one nevertheless. DC can continue to ignore it or write its way around it, but it might be best served by leaning into this unexpected continuity change. Explicitly giving Batman Jewish heritage wouldn’t break the character in any fundamental way. It could only add to his depth and give readers a new way to look at the beloved superhero.