He became captain in the Foot Guides on 20 January 1799 and was promoted to chef de bataillon (major) on 17 February 1800.

[3] During the occupation of Egypt, the French generals formed two quarreling factions, those supporting the army commander Jacques-François Menou and those backing Jean Reynier.

Fearing that the opposing faction was about to depose him, Menou sent Jacques Zacharie Destaing with more than 350 soldiers and a cannon to surround Reynier's house on 13 April 1801.

An officer named Novel burst into the room where Reynier, François Étienne Damas and others were meeting and demanded that they surrender their weapons.

Bloodshed was avoided when a quick-thinking Meunier ordered his Foot Guides out of the room, then politely requested Reynier and his colleagues to submit to their commander-in-chief.

[1] On 11 October 1805, the 9th Light Infantry fought at the Battle of Haslach-Jungingen as part of Dupont's 1st Division of Marshal Michel Ney's VI Corps.

During this remarkable action, Dupont's 5,350 infantry, 2,169 cavalry and 18 guns held off 25,000 Austrians under Karl Mack von Leiberich.

[11] On 17 October 1806, the 9th Light Infantry fought in the Battle of Halle as part of Marie François Rouyer's brigade.

[18] At the Battle of Uclés on 13 January 1809, the division under François Amable Ruffin, formerly Dupont's, conducted a successful envelopment of the Spanish right flank.

[20] During the Battle of Talavera on 27–28 July 1809, Marshal Victor ordered Ruffin's division to conduct a night assault on the British-held Cerro de Medellin.

On the other hand, the 9th Light rapidly crossed the ravine and ascended the Cerro, striking the 7th Line Battalion of the King's German Legion.

The German unit had its pickets placed too close so that the battalion was overrun within a few minutes, losing 150 casualties including many prisoners.

As the two leading French battalions reached the top of the Cerro, the British division commander Rowland Hill rode up to them and was nearly captured.

Though an officer with him was killed, Hill galloped away in the dark, rallied a nearby brigade and led them to retake the hilltop.

A few days later, Talavera de la Reina was abandoned by the Spanish; Meunier and other wounded prisoners in the hospitals were liberated by the French.

[6] He directed the converged grenadier battalion of Jean François Leval's division at the Battle of Barrosa on 5 March 1811.

[22] On 1 March 1812, Meunier led the 1st Brigade in Nicolas François Conroux's 1st Division of Marshal Jean-de-Dieu Soult's Army of the South.

[1] In the Battle of Lützen on 2 May 1813, Meunier led a brigade in the 36th Infantry Division under Henri François Marie Charpentier in Marshal Jacques MacDonald's XI Corps.

[24] At about 5:30 pm, Charpentier's division came into action on the extreme French left flank, preceded by a bombardment from the corps artillery.

[34] At the Battle of Brienne on 29 January, Meunier's division attacked the village of Brienne-le-Château after nightfall but was unable to oust its Russian defenders.

[39] At the Battle of Montmirail the next day, Meunier's division was engaged in a bitter struggle against the Russians at the village of Marchais-en-Brie.

[43] At the Battle of Craonne on 7 March, Ney attacked prematurely on the right flank without artillery support, throwing Meunier's division at the Chemin des Dames ridge near Ailles around 9:00 am.

At 11:30 am after the French guns belatedly began bombarding the Russian position, Ney personally led Meunier's depleted division forward and they secured a foothold on the high ground.

Despite cavalry support, Meunier's troops were driven off the ridge at 1:00 pm, but an hour later they won another foothold.

[3] During the Battle of Laon on 9 March, Ney's corps fought all day over the hamlet of Semilly, capturing it and being driven out more than once.