Hospital director Pierre Nuty said she died early yesterday at the Bruyn hospital, where she was admitted in March 1980.
Cousin Armelle Blanchard said that while Blanchard could no longer talk, she was in good health and would smile when people spoke to her.
She was the last survivor of a family of 13 siblings.
St Barts legislator Victorin Lurel said Blanchard had earned the nickname “Douchy”, which means “Sweets”, because of how she treated others.
S Blanchard was born in St Barts on February 16, 1896 and lived most of her life in a convent in Curacao before returning home.