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Palatinate Campaign

France’s new reformed army, including their alliance commitment of an additional 35,000 troops had trained and marched to the Palatinate-Rhine border during spring and crossed south of the Neckar river. There it merged with the allied forces of the Duke of Wurttemburg. They again joined with Austro-Bavarian forces (included those that had retreated from the Battle of Hanau) as they marched north and joined yet again with allied forces from Hesse-Darmstadt. The combined army would then move north and occupy Hesse-Kassel.

At the same time, the French army on the Northern Rhine would push across again to recapture the Prussian provinces of Cleaves and Mark and continue east, aiming to join the southern army in Hesse for a new offensive in Hanover.

Battle of Frankfurt on the Main

Having been forewarned of the French army to his south, the Duke of Brunswick retreated after his victory at Hanua to gather troops to face this threat.

A French force of 35,000 was led by Victor Francois, the 2nd Duc de Brogile, and was assisted by 6,000 Austro-Bavarian forces, 4,000 Hesse-Damnstadt and 4,000 Wutternburg forces, for a total force size us 49,000.

Facing them was 12,000 Hanover forces, 5,000 British regulars, 8,000 Hessians, 2,500 troops from Schamburg-Lippe, and 500 from Brunswick-Wolfembutte for a total force of 28,000 led by the Duke of Brunswick.

On June 6th, both sides moved quickly to occupy the city of Frankfurt on opposite sides of the Main river, and settled into a series of fierce skirmishes and artillery duels that devastated the town, and inflicted numerous civilian casualties. On the second day of fighting it became clear to the Duke of Brunswick that he would be surrounded if he did not retreat and broke clear of the city and fell back to Marburg with the French army in pursuit.

French and Allied forces: 3,500 dead and wounded.
Hanover and Allied Forces: 2,800 dead and wounded, 10 guns captured.
Civilian casualties: Estimated to be at over 1,500.

Clear French Victory.

On June 10th, after receiving word of the defeat at Frankfurt and France’s invasion into Hesse, William VIII, Langraf of Hesse-Kassel, already aged, ill and depressed form the earlier loss of his son in the Prussian battles, passed away leaving only regents in charge of Hesse.

The town of Frankfort was devastated, and with the deaths and fleeing of many of its residents, it would cease to remain a free imperial city at the wars end, opting instead to merge into its surrounding province in exchange for recovery assistance.