The 3rd Cuirassier Regiment () was a cavalry regiment of the French Army, later reequipped as an armored regiment.
Ancien Régime
Timoléon de Sercourt d’Esclainvilliers inherited his father's company of Light Horse in 1635, when he was three years old. The same year in May, Cardinal Richelieu decided to reorganize the French cavalry, Esclainvilliers' company became part of the Cardinal Duc regiment. It fought in the Battle of Rocroi as a part of that unit. During this time the regiment became the Esclainvilliers Cavalry, the ancestor of the 3rd Cuirassier Regiment.
The regiment distinguished itself fighting in Flanders in 1650. In 1652, under the command of Turenne, it fought against the fronders in Paris and was present at Stenay. The unit was renamed as the Commissaire General Regiment in April 1656.
The regiment provided up to six companies in 1665 for the reconquest of Flanders, took part in the siege of Maastricht in 1673, and then served as a garrison for a time in Franche-Comté before it returned to Flanders. It stayed in Flanders during both the Nine Years' War and the War of Spanish Succession.
The regiment joined the Army of the Rhine at Landan in 1742 and distinguished itself at Ratisbon. It was sent to the Army of the Alps in 1746, but the war ended the next year with the Peace of Aix-la-Chapelle. During the Seven Years' War it was sent to Saint-Lô in 1762 to defend the French coastline. In 1791, the regiment was renamed as the 3rd Régiment de Cavalrie. In 1802/03 the Regiment was retitled the 3rd Cuirassiers.
The Revolutionary Wars
During the French Revolutionary Wars and the Napoleonic Wars, the regiment fought in the battles of Valmy, Marengo.
Napoleonic Wars
It took part in the battles of Austerlitz, Jena, Eylau, Heilsberg and Friedland.
In 1807 a detachment was sent to Spain where it was combined with detachments from the 1st and 2nd Cuirassiers and the 1st and 2nd Carabiniers to form the 1st Provisional Heavy Cavalry (designated as the 13th Cuirassiers at the end of 1808).
From 1809 on the regiment served in the battles of Eckmühl, Essling, Wagram, Ostrowono, Smolensk, Borodino, Dresden, Liebertwolkwitz, Leipzig, Champaubert, Fère-Champenoise.
During the First Restoration (1814), the regiment was given the designation of the Régiment de Cuirassiers du Dauphin. With the return of Napoleon I in 1815, the regiment was renamed the 3eme Régiment de Cuirassiers. It fought at Ligny and Waterloo. It was disbanded with the Second Restoration on 25 November.
July Monarchy and Second Empire
The final fall of the Bourbons and the establishment of the July Monarchy mean that the regiment once again became the 3rd Cuirassier Regiment. Between 1830 and 1869, the regiment was in garrison in Lyon and Lunéville.
When war was declared between France and Prussia in 1870, the regiment was garrisoned in Lunéville. The regiment entered Haguenau on 2 August, then Reichshoffen, where it fought in the Battle of Wörth. There it took part in the great cavalry charge. The remains of the regiment withdrew in good order and arrived at Saverne on 7 August and after a short period of recovery there joined the Army of Châlons on 20 August 1870. After passing through Floing the regiment took part in the Battle of Sedan on 1 September. Together with the rest of its division, the regiment then became prisoners of the Prussian army.
Following release, the regiment was sent to Paris on the evening of 4 March 1871. Although designated as a "marching regiment" (ad hoc unit) it became the 3rd Cuirassier Regiment again on 1 April 1871.
World War I
The regiment crossed the Franco-Belgian border on 6 August and took part in the operations around Florenville. It also took part in engagements of the Great Retreat and the following Race to the Sea. At this early stage in the war it was still a horse-mounted formation wearing the plumed helmets and cuirasses of the Napoleonic period, with the colorful uniforms of peacetime. From November 1914 to March 1918 the 3rd Cuirassiers saw spells of service as temporarily dismounted cuirassiers a' pied in the trenches, in the North, the Somme, and Champagne. Except for these brief intervals, the 3rd retained its historic role as mounted heavy cavalry for most of the war, remaining in reserve behind the lines. Five of the other cuirassier regiments were fully converted to infantry after the opening stages of conflict.