A cache of passionate letters and works documenting a once-secret love between one of the greatest novelists of his time, Marcel Proust (1871-1922), and the eminent composer Reynaldo Hahn (1874- 1947), have realised €750,000 at Sotheby’s Paris. Largely unseen, they have impeccable provenance, having coming to sale direct from Proust’s family.

Highlights included unpublished proof copies of his greatest works, Proust’s famous footnotes describing his disagreements with Ruskin and the large collection of 138 letters from the publisher Gaston Gallimard to Proust.

The collection shed a new light on Proust through 70 lots of literary manuscripts, letters and books with envois, constituting a genuine biography.

The top lot of the archive was a very early draft of one of the finest passages from Côté de chez Swann, describing the hero's walk along the Vivonne (lot 160, €132,500).

One of the great discoveries of this collection was the striking personality of Reynaldo Hahn, Marcel Proust's great love and lifelong friend, seen through their amusing correspondence. One letter describes Proust's day (lot 140, €6,875), while a touching series, almost entirely unpublished, illustrates the strong bond between the two men (lot 141, €19,375) and a beautiful melancholic letter full of feeling speaks of the death of Mallarmé (lot 145, €4,500).

One of the most fought-over lots was a pencil portrait of Marcel Proust on his deathbed by Jean-Bernard Eschemann, which finally fetched €45,000 (lot 196).

The session was also rich with lots illustrating Proust's daily life, including a 1911 note from the Grand Hôtel in Cabourg, the town on which he based Balbec (lot 169, €9,000).