Henri Lassan is a French Army officer, the commandant of the fortress at Arcachon in Sharpe's Siege.
Novels
He was regarded as a gentleman by his men, who allowed the families of the gun crews quarters inside the fort where no women should be.
His desire was to enter the priesthood after the war's end, but was duty bound to fight as a soldier until the last shot was fired. He was a canny enough tactician to entirely fool the British naval captain, Horace Bampfylde as to the strength of his command.
He escaped Teste de Buch afterSharpe took the fortress, and led General Calvet's men through the dunes to a flank attack against the British that came within a hair's breadth of succeeding.
His father had been the comte de Lassan, a title going back some 800 years, and had died under the guillotine, but Henri had never used nor been tempted to use the title that was rightfully his. After the war, he returned to Chateau Lassan in Normandy, where his mother, the dowager comtessa, set about making a match between him a daughter of the local gentry to secure the title with an heir despite his voiced preference for the priesthood.
He told his sister, Lucille, of his command, of the greenjackets who fought like demons, how Sharpe had failed to kill him when he had the chance, and Henri's nightmare was that one day he would.
He finally agreed to marry, and the family hosted a betrothal ceremony, beggaring what remained of the estate to do so. The evening after the party, men in green coats and carrying muskets, came to the chateau and asked for him by name. They brought their weapons to bear, and trying to shield his mother with his body, he was shot in the back, and died instantly. His mother died as well, with a bullet to the head.
After his death, his murderers chopped off two fingers of his right hand, to make it correspond with a testimony previously delivered by Pierre Ducos. To keep Lassan, vaunted as an honorable man, from speaking and unraveling one of his tortuous plots, Ducos had ordered him killed. (Sharpe's Revenge)
Television
Stephene Cornicard as Henri
In the television movie, Henri Lassan is called Henri Maillot, the name, in the novel, of the man who initially delivers the treasure to Ducos, and was summarily murdered by him. In the movie, Henri was present immediately before Ducos stole Napoleon's treasure, rather than just being roped in to the plot by Ducos' testimony. He also mentioned the name Ducos to his sister, Lucille, as well as that of Sharpe.
No mention was made of his title or the ancestral home, the farm in the movie seemed substantially less than as described in the book, nor was his mother present.
He is portrayed as a man living with a guilty conscious, agonizing about having failed in his duty by riding away when Ducos took over the treasure shipment.
He is murdered at his home by men sent by Ducos, who made sure to repeat Sharpe's name as they fled, for the benefit of any witnesses - in this case, Henri's sister.