In the early years of the French Revolution Sahuc was appointed to lead a Chasseurs à Cheval regiment and later commanded a brigade.

Later he transferred to the Army of Sambre-et-Meuse and was appointed Chef de brigade (colonel) of the 1st Chasseurs à Cheval Regiment on 10 July 1794.

That same day at Vöcklabruck, with Sahuc commanding the 48th Line and 14th Light Infantry plus the 1st and 20th Chasseurs, the French captured Austrian general Franz Löpper, two cannons, and many foot soldiers.

[2] In the War of the Third Coalition, he served in a division that included the 15th and 17th Dragoon Regiments, which lost their eagles and many troopers at the Battle of Haslach-Jungingen on 11 October 1805.

[7] On 2 December 1805, Sahuc fought at the Battle of Austerlitz in François Antoine Louis Bourcier's 4th Dragoon Division.

[16] Once the French seized the gate, the cavalry burst into the streets and helped capture the Owstein Infantry Regiment No.

[2] In the War of the Fifth Coalition, Sahuc found himself leading the Light Cavalry Division of the Army of Italy under Eugène de Beauharnais.

[20][21] In the Battle of Sacile on 16 April, Eugène refused to fully commit Sahuc's division because of the Austrian cavalry superiority.

After Eugène ordered a retreat, Sahuc demonstrated in front of the Austrians, assisting the withdrawal of the divisions of Paul Grenier and Jean-Baptiste Broussier.

The light infantry formed square and successfully repelled an Austrian cavalry division, but they were being pounded by a massed battery of 24 cannons.

[23] The bombardment caused Dessaix's men serious loss and 20 French guns arrived just in time to reply to the Austrian artillery.

In the meantime, Sahuc unwisely posted his division in such a way that some of the cannonballs missing the infantry squares hit his troopers.

[24] The second time the Austrian cavalry attacked, Sahuc's light horse and Pully's dragoons countercharged and routed them.

[26] With his cavalry rendered impotent, Archduke John of Austria could only mount a passive defense, which resulted in his eventual defeat.

[28][29] While Emmanuel Grouchy and Louis-Pierre Montbrun's cavalry on the right flank defeated the Austrians opposed to them, his division guarded the left.

As the Austrian army withdrew at the end of the battle, Sahuc's cavalry launched a pursuit which soon came upon some Hungarian insurrection (militia) infantry formed in squares.

Though the raw Hungarians fired a scattered volley, they managed to fend off the first charge because the French horsemen attacked in a disorderly fashion.

The assault ended in failure with the French fleeing back to their starting positions after suffering heavy losses.

[34] On 6 July, his cavalry guarded the flanks of Jacques MacDonald's famous hollow square as it attacked the Austrian center.