Joannes, or John de Serres, a learned French Protestant, was born about the middle of the sixteenth century. He acquired the Greek and Latin languages at Lausanne, and devoted himself to the study of the philosophy of Aristotle and of Plato. On his return to France he studied divinity, and in 1574 he began to distinguish himself by his writings, but was obliged to forsake his country after the dreadful massacre of St Bartholomew. He became minister of Nismes in 1582, but was never regarded as a very zealous Calvinist; he has even been suspected, though without reason, of having actually abjured the Protestant religion. He was one of the four clergymen whom Henry IV. consulted about the Catholic religion, and who returned for answer, "that Catholics might be saved."

He wrote afterwards a treatise in order to reconcile the two communions, entitled "De Fide Catholica, sive de Principiis Religiosis Christianae, communi omnium Christianorum consensu, semper et ubique ratis." This work was disliked by the Catholics, and received with such indignation by the Calvinists of Geneva, that many writers have affirmed that they poisoned the author. It is certain at least that he died at Geneva in 1598, at the age of fifty. His principal works are, 1. A Latin translation of Plato, published by Henry Stephens; 2. A treatise on the Immortality of the Soul; 3. De Statu Religionis et Republicae in Francia; 4. Memoire de la Troisieme Guerre Civile et derniers Troubles de France sous Charles IX. &c.; 5. Inventaire General de l'Histoire de France, illustre par le Conference de l'Eglise et de l'Empire; 6. Recueil des Choses Memorables venues en France sous Henri II., Francois II., Charles IX., Henri III. These three historical treatises have been justly accused of partiality and passion; faults which it is next to impossible for a contemporary writer to avoid, especially if he bore any part in the transactions which he describes. His style is exceedingly incorrect and inelegant; his mistakes and mistakements of facts also are very numerous.