Youngest person named "Oldest living person"

The youngest person to accede to the title of world's oldest living person was Anne Marie Carsterson, born Jensen in Vordingsborg, Denmark, on 24 January 1849 and aged 107 years 327 days when the previous world's oldest living person, Jennie Howell, died on 16 December 1956. As of 20 March 2017, based on the most recent verification of longevity record claims received by Guinness World Records since 1955 and claims researched by the Gerontology Research Group among the world’s population of people born after 1840, the record remains unbeaten. Mrs Carsterson, who had emigrated from Denmark to the USA in 1869, lived to be 109 years 65 days, passing away on 30 March 1958 in Nebraska, USA.

Improved life expectancy in parts of the world, along with a larger population base and improved access to birth and death data means that Mrs Carsterson, who acceded the title aged 107 years 327 days, wouldn't even be in the top 600 oldest living persons in 2017 – and this only just over 60 years since reliable longevity record keeping began.