Are there Jews named Baum? Sure. Is Baum a specifically Jewish name? No.
According to Wikipedia:
[L Frank] Baum was born in Chittenango, New York, in 1856 into a devout Methodist family. He had German, Scots-Irish, and English ancestry. He was the seventh of nine children of Cynthia Ann (née Stanton) and Benjamin Ward Baum...
Heck, just looking through the lists of Baums, there's a freaking Waffen-SS commander named Otto Baum.
His last name was (((Baum))), wasn't it?
(I can't find any source today that Baum is indeed jewish, but it appeared in my list of jewish surnames when I compiled it a few years ago).
The problem is that many American Jewish names are also German names.
All evidence points to him being not religious, but raised in a Methodist family, with no Jewish ancestry.
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Baum is just German for "tree."
Are there Jews named Baum? Sure. Is Baum a specifically Jewish name? No.
According to Wikipedia:
Heck, just looking through the lists of Baums, there's a freaking Waffen-SS commander named Otto Baum.
Tannenbaum song incoming