Historical clue formulations

• Who once quipped “I never forget a face, but in your case I’ll be glad to make an exception" — 2023-10-22
• Mustachioed Marx brother — 2022-05-23
• Whom some novelty disguises imitate — 2013-05-02
• The mustachioed brother — 2000-03-13
• Julius, familiarly — 1994-02-26