Pierre-Henri, a learned Greek scholar, was born at Dijon in 1726. At an early age he gave himself up to the study of Greek and English, and made himself known by translations from both of these tongues. He greatly extended his fame by his controversy with Voltaire on the subject of that writer's Philosophie de l'Histoire. This work was thought highly dangerous by the orthodox, and Larcher was urged to reply to it, which he did in his Supplement à la Philosophie d'Histoire. He was thought to have the best of the argument; but his antagonist, in a rejoinder, entitled Défense de mon Oncle, overwhelmed him with ridicule and persiflage. Larcher incisively adopted the same style in his Réponse, but in that vein he was no match for his opponent, and to all the future scorns of Voltaire he did not dare to reply. In 1775 he published his Mémoire sur Vénus, which was crowned by the Academy of Belles-Lettres. Three years later he became a member of that society, and contributed to its Transactions some valuable papers, chiefly on the vases and festivals of some of the nations of ancient Greece. When the Imperial University was instituted, Larcher was made titular professor of Greek; but he was then eighty-three years of age, and could only do duty by deputy. He died in 1812 of the effects of a fall.

Of Larcher's translations may be mentioned the Electra of Euripides; Xenophon's Apologia and Anabasis; Pope's Martius Scriblerus. His name, however, is kept alive chiefly by his Herodotus, which appeared in 1786. From the first it was condemned as clumsy and inelegant, though correct in the main; but the value of the geographical and chronological notes was acknowledged as great. Even these have been now, to a great extent, superseded by the later researches of Renssell, Niebuhr, Dahlmann, Jäger, and Bähr.