Marie Ladon, Vicomtesse de Graçay, was the daughter-in-law of the Comte de Graçay. She married his second son, Marcel, before he was killed at Aspern. The Comte did not approve of the union, but after his son's death, he took pity on Marie and sheltered her in his residence, the Chateau de Graçay.
Marie was the daughter of a Normandy peasant. He owned the land he worked, but he was a peasant nonetheless. She married a soldier, Marcel Landon, son of the Comte de Graçay. The Comte tolerated the marriage, but did not approve of it. When her husband was killed fighting in Napoleon's army, Marie came to live with the Comte.
In the winter of 1810-1811, the Comte and Marie sheltered Hornblower, Bush, and Brown, who had escaped from French custody. During this time, Marie entered into what would be the first of two relationships with Hornblower. Marie posed the only serious threat to Hornblower's relationship with Barbara, as Hornblower in later years thought often of his time in France with Marie and the Comte. In Lord Hornblower, Hornblower returns to Marie while Barbara is in Vienna with her brother the Duke of Wellington. During this time, he and Marie resume their relationship, and Hornblower contemplates giving up his life in England to remain with Marie and the Comte. It is not known if Hornblower would have followed through with what may have been an idle fantasy, as Marie is killed in a skirmish with Republican French troops during the Hundred Days campaign.