Another Walloon regiment, Vierzet was raised 25th March 1757 for service with the French army. It had two battalions and was recruited in the Bishopric of Liège by Colonel Charles Albert Baron Vierzet. In the 1759 État Militaire the regiment ranked 119th.
About the only detailed account I can find of this regiment is on Kronoskaf; it seems the records and archive of the regiment were lost as a result of a riot in 1769 in Bruges and after a later surprise attack on Namur, so little accurate information is available on its early history. A somewhat unreliable history was published in 1847 in German, as the regiment subsequently passed to the Austrian service in 1762, becoming Infantry Regiment 58.
Please note further details of both Horion and Vierzet are given in the account that Simon Modaff kindly posted in the comments to Regiment Horion below; the text he cites I have posted with that regiment.
The flags feature the column of Liège, as also shown on the flags of Horion which I previously posted. The flag details are taken from the French 1757 MS image.
To summarise the history as related on Kronoskaf, by August 1757 the regiment was in garrison in Givet and Charlemont in Hainault. By 1758 the regiment was with Broglie's corps in Hessen. On July 10th 1760 it was at the combat of Corbach, attached to the vanguard under Baron de Clausen. In October it was part of M. d'Aubigny's detachment. On July 16th 1761 it was at the battle of Vellinghausen, in Bouillon's Brigade in the second line of the centre of Soubise's army. On the 28th August, the regiment was roughly handled when it was attacked in Dorsten. Fighting took place in the streets and the town place before the Allies finally captured the town, along with Soubise's bakery and the 1st battalion of Vierzet, with its colonel. On October 16th the 2nd battalion of the regiment was at the battle of Clostercamp, deployed on the far right.
By March 1762 the regiment was part of the Prince de Condé's Army of the Lower Rhine. Returning to France in November, on the 25th it was disbanded but then in January 1763 sent to Brussels and taken into the service of the Austrian Empire. Its commander the Baron de Vierzet became a major-general and the regiment's proprietor. The regiment was enlarged by further recruitment in Liège. According to Christopher Duffy, the Walloon regiments were some of the most dependable units in the Austrian army.
And this is the uniform in 1757:
