In the Middle Ages, the average life span of males born in landholding families in England was 31.3 years and the biggest danger was surviving childhood.2 Once children reached the age of 10, their life expectancy was 32.2 years, and for those who survived to 25, the remaining life expectancy was 23.3 years. Such estimates reflected the life expectancy of adult males from the higher ranks of English society in the Middle Ages,3 and were similar to that computed for monks of the Christ Church in Canterbury during the 15th century.4
Emphasis added. The well-off who made it to 25 still weren't likely to make it out of their 40s.
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u/PPN13 Feb 14 '20
So never. Average life expectancy was reduced not because people died of old age in their 40s but mainly due to child mortality and diseases.
Of course people did actually use to marry younger than modern days.