Raimondo di Sangro, the alchemist prince of Sansevero

Few figures have fired the Neapolitan imagination as much as Raimondo di Sangro, seventh Prince of Sansevero. Born in Torremaggiore, in Apulia, on 30 January 1710 and died in Naples on 22 March 1771, he was a soldier, man of letters, inventor and patron. His life unfolded between the family palace on Piazza San Domenico Maggiore and the private chapel he transformed into one of the most enigmatic monuments in Europe. Around him the city soon built a dark legend, fed by the fumes and the night-time lights of his laboratories.

An encyclopaedic education

Having lost his mother early and been placed in the care of his grandfather, young Raimondo was sent to study in Rome at the Seminario Romano run by the Jesuits. There he received a remarkably broad education: ancient and modern languages, philosophy, mathematics, natural sciences, military architecture and pyrotechnics. Back in Naples he took up his title and entered the intellectual life of the kingdom of Charles of Bourbon. He was admitted to the Accademia della Crusca under the name «Esercitato», a sign of a reputation that reached well beyond southern Italy.

In his palace he set up a private printing press which, according to contemporary accounts, could print several colours in a single pass. From those presses came, in 1751, the «Lettera apologetica», a treatise on quipu, the knotted cords the Incas used to record information. The work, full of digressions on the nature of signs and the transmission of knowledge, was condemned by the Church authorities and placed on the Index of Forbidden Books.

Inventions and freemasonry

Sources of the time credit him with a surprising list of experiments: waterproof fabrics for the army, a carriage able to travel on water, new pigments for painting, fireworks in unprecedented colours. The prince also claimed to have produced an «eternal lamp», a flame that burned without being consumed. Of many of these inventions only the description survives, yet they reveal a mind that combined the experimental curiosity of the Enlightenment with the Baroque taste for the marvellous.

Raimondo was also Grand Master of Neapolitan freemasonry around 1750. When in 1751 Pope Benedict XIV renewed the condemnation of the lodges and the king banned their meetings, the prince recanted and handed the names of the members to the sovereign. The choice, dictated by political prudence, earned him the hostility of many brethren, but it did not extinguish his fame as a man bound to secret wisdom.

The birth of a dark legend

Ordinary people saw the palace windows lit late into the night and heard talk of alembics, mysterious substances and human bodies. So arose tales of pacts with the devil, of servants sacrificed to experiments, even of a prince who had himself dismembered in order to rise again. Benedetto Croce, in his «Storie e leggende napoletane», showed how popular memory had turned the scholar into a necromancer. These stories have no documentary basis, but they reveal how a city looked upon a kind of knowledge it did not understand.

Today Raimondo di Sangro is studied as a typical eighteenth-century scholar, poised between emerging science and the Hermetic tradition. His most visible legacy remains the Sansevero Chapel, where art, symbol and experimentation merge into a unique iconographic programme. Visitors enter, in a sense, the very mind of the prince and his questions about life, death and knowledge.