Ambroise Paré

Apprenticed as a barber-surgeon at Hôtel-Dieu in Paris, Paré joined the French royal army during the Italian Wars. At the Siege of Turin in 1537, having run out of boiling elderberry oil used to cauterize gunshot wounds, he concocted a soothing balm of egg yolks, rose oil, and turpentine, discovering that wounds healed far better without brutal burning.

In 1552, he made the revolutionary medical breakthrough of tying severed blood vessels with silk thread (arterial ligature) during amputations rather than searing them with red-hot irons. Serving four French kings (Henry II, Francis II, Charles IX, Henry III), Paré survived the St. Bartholomew's Day Massacre protected by Charles IX himself.