John, was born at Stendall, in the old Marche of Brandenburg, in 1718. He was the son of a shoemaker. This wonderful man, to all appearance destined by his birth to superintend a little school in an obscure town of Germany, raised himself to the office of president of antiquities in the Vatican. His course of study appears to have been very desultory, but he spent two years in the university of Halle. After having been seven years rector of the school of Seehausen, near Salswedel, he went into Saxony, where he resided seven years more, and was librarian to Count Bunau at Nothenitz. When he left this place, 1754, he went to Dresden, where he formed an acquaintance with the ablest artists, and particularly with Oer, an excellent painter, and one of the best draughtsmen of the age. In that year he abjured Lutheranism, and embraced the Romish religion. In September 1755, he set out for Italy, and arrived at Rome in December following. His principal object was to see the Vatican library, and examine the ruins of Herculaneum.

Winkelmann carried with him into Italy a sense of beauty in art, which led him instantly to admire the masterpieces of the Vatican, and with which he began to study them. He soon increased his knowledge; and it was not till after he had thus purified his taste, and conceived an ideal of ideal beauty, which led him into the greatest secrets of art, that he began to think of the explanation of other monuments, in which his great learning could not fail to distinguish him. In 1756 he planned his Restoration of Ancient Statues, and a larger work on the Title of the Greek Artists; and he designed an account of the galleries of Rome and Italy, beginning with a volume on the Belvidere statues, in the manner of Richardi, who, he says, only ran over Rome. He also intended a history of the corruption of taste in art, the restoration of statues, and an illustration of the obscure points of iconography. All these different essays led him to his History of Art, and his "Monumenti Inediti." It must be confessed, that the first of these works has not all the clearness and precision that might be expected in its general plan and division of its parts and objects; but it has enlarged and extended the ideas both of antiquaries and collectors. The description of the gems and sculptures of the Stosch cabinet contributed not a little to extend Winkelmann's knowledge. Few persons have opportunities of contemplating such vast collections. The engravings of Lippet and Count Caylus are all that many can arrive at. Winkelmann's "Monumenti Inediti," of which he had been the third volume in 1767, seem to have secured him the esteem of antiquaries. Had he lived, we should have had a work long wished for; a complete collection of the hieroglyphics discovered from the time of Bartoli to the present, the greater part of which were in the possession of Cardinal Albani.

When Cardinal Albani succeeded to the place of librarian of the Vatican, he endeavoured to procure a place in the Borew department for Winkelmann, who refused a cayery because he would not take the tonsure. In 1761 the elector of Saxony gave him, unsolicited, the place of Counsellor Richter, the direction of the royal cabinet of medals and antiquities at Dresden. Upon the death of Venuti, 1762, he was appointed president of the antiquities of the apostolic chamber, with power over all discoveries and exhibitions of antiquities and pictures. This is a post of honour, with an income of 160 scudi per annum. He had a respect of the place of president of antiquities in the Vatican, about to be created, at sixteen scudi per month, and was named corresponding member of the Academy of Inscriptions. The king of Prussia offered him, by Col. Quintus Icilius, the place of librarian and director of his cabinet of medals and antiquities, vacant by the death of Gautier de la Croze, with a handsome appointment. He made no scruple of accepting the offer; but when it came to the pope's ears, he added an appointment out of his own purse, and retained him at Rome.

In April 1768, he left Rome to travel with Cavaceppi over Germany and Switzerland. When he came to Vienna, he was so pleased with the reception he met with, that he made a longer stay there than he had intended. But being suddenly seized with a secret uneasiness and extraordinary desire to return to Rome, he set out for Italy, deferring his visits to his friends in Germany to a future opportunity. As he passed through Trieste, he was assassinated, June 8, 1786, by a wretch named Arcangeli, a native of Campiglio, a town in the territory of Pistoia, with whom he had formed an acquaintance on the road. This miscreant had been condemned for a robbery to work in fetters four years, and then to be banished the Austrian territories on an oath never to return. He had obtained a mitigation of one of his sentences, and retired to Venice; but changing his quarters backwards and forwards, he was so reduced in circumstances that he at length took up his lodgings at the inn where Winkelmann happened to arrive. Arcangeli paid such assiduous court to him, that he entirely gained his confidence; and having been favoured with a sight of the valuable presents which he had received at Vienna, formed a design to murder and rob him. He bought a new sharp knife on purpose; and as Winkelmann (who had in the most friendly manner invited him to Rome) was sitting down in his chair, early in the morning, he threw a rope over his head, and, before he could disengage himself, stabbed him in five different places. He had still strength to descend to the ground-floor and call for help; and being laid on a bed in the midst of the most violent pain, he had composure sufficient to receive the last sacraments, and to make his will, in which he appointed Cardinal Albani his residuary legatee, and expired in the afternoon. The murderer was soon after apprehended, and on the 20th of June was executed on the wheel, opposite the inn where he had committed this atrocious deed.