Nicolas-Claude Fabri de Peiresc (1 December 1580 – 24 June 1637), often known simply as Peiresc, or by the Latin form of his name Peirescius, was a French astronomer, antiquary and savant, who maintained a wide correspondence with scientists, and was a successful organizer of scientific inquiry. His research included a determination of the difference in longitude of various locations in Europe, around the Mediterranean, and in North Africa.
Peiresc's father was a higher magistrate and city surgeon in Provence from a wealthy noble family, who with his wife fled their home town of Aix-en-Provence to avoid the plague raging there, settling in Belgentier in Var. Peiresc was born in Belgentier and educated in Aix-en-Provence, Avignon, and at the Jesuit college at Tournon. At Toulon, he first became interested in astronomy. Studying law and becoming interested in archaeology, he travelled to Italy, Switzerland and France in 1599, and finally finished his legal studies in 1604 at the University of Montpellier. It was also in 1604 that he assumed the name Peiresc after a domain in Alpes-de-Haute-Provence (now spelled Peyresq) which he had inherited from his father, although he himself never visited it.
After receiving his degree, he travelled to Paris (in 1605-1606, with his patron Guillaume du Vair, president of the Parlement of Provence), London and Flanders before returning to Aix in 1607 to take over his uncle's position as conseiller in the Parlement of Provence under du Vair. He held this post until 1615.