His father had been owner of the Vichy Saint-Yorre mineral water springs, and the family fortune assured him an easy life.

On luxury liners and the Orient Express he carried off the dandy role, with spa visits to nurse fragile health.

Poèmes par un riche amateur, published in 1908, received Octave Mirbeau's vote for prix Goncourt.

Three years later, his novel Fermina Márquez, inspired by his days as a boarder at Sainte-Barbe-des-Champs at Fontenay-aux-Roses, had some prix Goncourt votes in 1911 but did not win; nonetheless, it is still considered to be a minor classic of French literature and one of Larbaud's best known works.

At home in Vichy, he saw as friends Charles-Louis Philippe, André Gide, Léon-Paul Fargue and Jean Aubry, his future biographer.