Rossbach French Flags Project - Regiment Beauvoisis

First raised in 1667, Beauvoisis had 2 battalions. The grenadier company distinguished itself in the affair at Weissenfels along with the grenadier company of St Chamond; see the entry for St Chamond below for a short account of the action. The regiment was at Rossbach, brigaded with Rohan-Montbazon Infanterie, and was the fourth regiment back in the centre column (the reserve). It was at Sandershausen in 1758, where it suffered heavy casualties, and then at Lutterberg, where it was not heavily engaged. It was involved in the bloodless and somewhat underhand capture of Frankfurt in January 1759. At Bergen in April 1759 the regiment performed very well, driving back the allied attack with the bayonet. After that until the end of the war it was stationed on the coast of Brittany.  [Details from Kronoskaf and C. Duffy's Prussia's Glory.]

The flags as depicted were carried by this regiment from 1685 to 1791.

And this plate shows the uniform and flags in 1757:

Rossbach French Flags Project - Regiment Rohan-Montbazon

First raised in 1634, Rohan-Montbazon had 2 battalions.  The regiment was at Rossbach (brigaded with Beauvoisis Infanterie), and was the third regiment in the centre column (the reserve) behind Provence and Poitou infantry regiments. It suffered heavily, losing 11 officers killed and 18 wounded. At Sandershausen in 1758 the regiment was battered by the Hessian attack, and, having used up all its ammunition, had to resort to the bayonet. Casualties were very heavy; 66 officers and 778 men were killed or wounded. At Lutterberg later that year the regiment was luckier and little engaged. In January 1759 it was involved in the relatively bloodless coup that seized the city of Frankfurt, which the French then held for the rest of the war. At Bergen in April 1759 along with Piemont and Royal Roussillon the regiment drove the allies back with the bayonet. In the last few years of the war the regiment garrisoned the Channel coast. [Details from Kronoskaf and C. Duffy's Prussia's Glory.]

The flags as depicted were carried by this regiment from 1745 to 1759.

And this plate shows the uniform and flags in 1757: