Cloris Leachman was 54 in History of the World: Part I when she played the character 'Madame Defarge'.
That was over 43 years ago in 1981.
In 2021 she died aged 94, starring in 141 films in her career, 95 of those after History of the World: Part I was first released. If she were alive today she would be 98.
In History of the World: Part I, I think Cloris Leachman looks: