The count -- whose full name was Jean Bruno Wladimir François de Paule Lefèvre d’Ormesson but went by the nickname Jean d'O -- wrote around 40 largely autobiographical novels.
Born in Paris on 16 June, 1925, d'Ormesson spent his childhood as the son of a diplomat, in Germany, Romania and Brazil.
His literary career took off with the publication of La Gloire de l'Empire (The Glory of the Empire) in 1971. His book was awarded the prestigious Académie Francaise prize.
Hailed by President Emmanuel Macron as a "prince in the world of literature" ("un prince des lettres"), d'Ormesson became the youngest member of the Académie Française in 1973.
Il était le meilleur de l'esprit français, un mélange unique d'intelligence, d'élégance et de malice, un prince des lettres sachant ne jamais se prendre au sérieux. L'œil, le sourire, les mots de Jean d'Ormesson nous manquent déjà.Emmanuel Macron (@EmmanuelMacron) December 5, 2017
He made his cinema debut aged 87 in 2012 playing former Socialist president François Mitterrand in a comedy, Haute Cuisine, based on the true story of the head of state's chef.
D'Ormesson had been a regular guest at Mitterrand's table.
Thin, elegant with mischievous blue eyes, the 'dandy' d'Ormesson was a frequent guest on French television.
Little known abroad because his novels were not translated, he was honoured in 2015 by the publication of his works by the Pléiade publishing house.
After a protracted battle with bladder cancer in 2013, his book Comme un chant d'espérance (Like a Song of Hope) pondered the origins of the universe and the vagaries of fate.
His last autobiographical book Je dirai malgré tout que cette vie fut belle (Nevertheless it was a beautiful life) was published in 2016.