The Vikings. Fellow tribesman Tony Curtis co-starred.
The question is hard to answer. Actors like Douglas, Curtis – Leslie Howard and Cornel Wilde also come to mind (and on the distaff side Hedy Lamarr, Zsa Zsa Gabor, Lauren Bacall) – didn’t hide the fact that they were Jewish, but they generally played macho or romantic lead roles against the stereotype, and I doubt their fan base understood the fact the way they might have if Eddie Cantor, Phil Silvers, or Eli Wallach were romancing the leading lady (or if they hadn’t adopted very waspy stage names).