Jean-Baptiste Willermoz (10 July 1730 – 29 May 1824) was a French Freemason and Martinist who played an important role in the establishment of various systems of Masonic high-degrees in his time in both France and Germany.
Jean-Baptiste Willermoz was born on 10 July 1730 in Lyon. He was the oldest of 12 children. He lived mainly in Lyon. He was the brother of Pierre-Jacques Willermoz, a physician and chemist who also worked on the Encyclopédie of Diderot and D'Alembert.
He was a manufacturer in silk and silver at Rue des Quatre-Chapeaux, and as a volunteer director of charities, he played an important role in the European freemasonry of his time. As such he was initiated at the age of 20 and became Venerable Master of his lodge at 23.
As a mystic, passionate about the secret nature of initiation, he contributed to the creation of the Regular Grand Lodge of Masters in Lyon and became its Grand Master in 1761. The Grand Lodge practised the seven Masonic high-degrees of the time, and added an eighth named "Scottish Grand Master, Knights of the Sword and the Rose-Croix." Willermoz founded in this setting, in 1763, together with his brother Pierre-Jacques, a lodge entitled "Sovereign Chapter of Knights of the Black Eagle Rose-Cross" which was devoted to alchemical research.
He was admitted to first grade in the Order of the Elus Cohens at Versailles in 1767 personally by Martinez de Pasqually on the recommendation of Bacon of Chivalerie and the Marquis de Lusignan. In May 1768 he was admitted to the Réaux-Croix. In 1772 he corresponded with the Strasbourg lodge of the Strict Observance. After the death of Martinez de Pasqually in September 1774, he engaged with his friend and Cohen-brother Louis-Claude de Saint-Martin to write a comprehensive review of the doctrine of the Elus Cohens, in the form of lessons, called "the Lessons of Lyon" to be held from 7 January 1774 to 23 October 1776. He said in a letter of 1780 to the Prince of Hesse that he was given the rank of Réau-Croix in the Order of Martinez Pasqually.