Well, to make a long story short, Walter Matthau was Jewish!
Since Walter Matthau's mother was Jewish, and in Orthodox Judaism and Conservative Judaism, those with a Jewish mother (or those who underwent a halakhic conversion) are considered Jewish, then that makes him Jewish. His father was Jewish too.
Walter Matthau (whose full birth name was Walter John Matthow) was born on October 1, 1920 in New York City, New York. Walter Matthau passed away on July 1, 2000 (aged 79).
He is best known for his role in The Odd Couple and his frequent collaborations with Odd Couple co-star Jack Lemmon, as well as his role as Coach Buttermaker in the 1976 comedy The Bad News Bears. He won the Academy Award for Best Supporting Actor for his performance in the 1966 Billy Wilder film The Fortune Cookie. Besides the Oscar, he was the winner of BAFTA, Golden Globe and Tony awards.
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