Turns out that it was from 1920 to late 1960 that resorts in the Catskills were popular with Jewish people from New York City, it was known as the Borscht Belt and here's some more info:
"It turned out all my favorite performers were veterans of the Catskills, Borscht Belt comedians, mostly Eastern European Ashkenazi Jews, who cut their teeth in the Catskills at resorts like Grossinger's, Brickman's, and The Overlook. The catalogue is thick of the funnymen with Catskills cred who flickered in my living room: Woody Allen, Morey Amsterdam, Bea Arthur, Milton Berle, Shelley Berman, Joey Bishop, Mel Blanc, Mel Brooks, Lenny Bruce, George Burns & Gracie Allen, Red Buttons, Sid Caesar, Billy Crystal, Rodney Dangerfield, Phyllis Diller, Totie Fields, Shecky Greene, Buddy Hackett, Danny Kaye, Alan King, Robert Klein, Harvey Korman, Jerry Lewis, Richard Lewis, Chico + Harpo Marx, Jackie Mason, Zero Mostel, Carl Reiner, Don Rickles, Joan Rivers, Rowan & Martin, Mort Sahl, Soupy Sales, Dick Shawn, Allan Sherman, Phil Silvers, Arnold Stang, David Steinberg, Jerry Stiller, The Three Stooges, Jonathan Winters, Ed Wynn, Henny Youngman; and on, as some above would say, ad libitum."
https://catskillsinstitute.northeastern.edu/
"It turned out all my favorite performers were veterans of the Catskills, Borscht Belt comedians, mostly Eastern European Ashkenazi Jews, who cut their teeth in the Catskills at resorts like Grossinger's, Brickman's, and The Overlook. The catalogue is thick of the funnymen with Catskills cred who flickered in my living room: Woody Allen, Morey Amsterdam, Bea Arthur, Milton Berle, Shelley Berman, Joey Bishop, Mel Blanc, Mel Brooks, Lenny Bruce, George Burns & Gracie Allen, Red Buttons, Sid Caesar, Billy Crystal, Rodney Dangerfield, Phyllis Diller, Totie Fields, Shecky Greene, Buddy Hackett, Danny Kaye, Alan King, Robert Klein, Harvey Korman, Jerry Lewis, Richard Lewis, Chico + Harpo Marx, Jackie Mason, Zero Mostel, Carl Reiner, Don Rickles, Joan Rivers, Rowan & Martin, Mort Sahl, Soupy Sales, Dick Shawn, Allan Sherman, Phil Silvers, Arnold Stang, David Steinberg, Jerry Stiller, The Three Stooges, Jonathan Winters, Ed Wynn, Henny Youngman; and on, as some above would say, ad libitum."
https://catskillsinstitute.northeastern.edu/
It's not the least charm of a theory that it is refutable. The hundred-times-refuted theory of "free will" owes its persistence to this charm alone; some one is always appearing who feels himself strong enough to refute it - Friedrich Nietzsche