| Jean du Teil | |
| Birth Date: | 7 July 1738 |
| Birth Place: | La Côte-Saint-André |
| Death Place: | Ancy-sur-Moselle |
| Spouse: | Marguerite-Louise Georgin de Mardigny |
| Children: | 3 |
| Father: | François du Teil |
| Relatives: | Jean-Pierre du Teil (brother) |
Jean, chevalier du Teil de Beaumont (1738, la Côte-Saint-André - 25 April 1820, Ancy-sur-Moselle), seigneur d'Ancy, was a French soldier in the Ancien Régime, Revolutionary and Imperial armies and theoretician of the use of artillery (the Gribeauval system).
The son of the artillery officer François du Teil (1704–1758), knight of the order of Saint-Louis, and of Marguerite de Chambaran (died 1758), he became an artillery officer himself at a very young age. Lieutenant-colonel of the régiment de Metz from 1785, he actively adhered to the principles of the Revolution, unlike his elder brother Jean-Pierre (who only accommodated rather than backed the Revolution, and was thus executed). From then on his rise within the army was meteoric: promoted to the rank of colonel in 1790, he soon became maréchal de camp (23 August 1792) then général de division (11 August 1793). He was made commander in chief of the artillery of the armée du Rhin (1792), then that of the armée des Alpes and armée d’Italie (1793), participating in the siege of Toulon.
Disdaining this last posting, he left it as soon as possible to go to command the artillery in the Alps, and the representatives of the people chose as his replacement then Brigadier General Napoleon Bonaparte, who gained his first successes in this role. Du Teil next served in the war in the Vendée in 1794. Discharged from the army as an aristocrat, he was only recalled to the ranks under the Consulate, when he was put in command of the place de Lille, then that of Metz. He was made a commander of the Légion d’Honneur then a knight of the order of Saint Louis. He retired in 1813 to the village of Ancy-sur-Moselle.
On 26 November 1771 he married Marguerite-Louise Georgin de Mardigny (daughter of François-Etienne, conseiller to the parliament of Metz, and of Barbe Lucie Besser de Charly) at Mardigny. They had 3 daughters: