The First Battle of Andernach between the West Frankish king Charles the Bald and the East Frankish king Louis the Younger took place on 8 October 876 near Kettig southeast of Andernach and resulted in Charles' complete defeat.

In the Treaty of Meersen, he additionally gained the eastern part of Middle Francia.

After Louis the German died, Charles again tried to extend West Francia to the east until the river Rhine.

On 8 October 876, this campaign culminated in the battle on a plain near Andernach which resulted in a decisive victory for Louis and stopped all further efforts of Charles to conquer Middle Francia.

In the Treaty of Ribemont, concluded by Louis the Younger and Charles' grandsons Louis III of France and Carloman of France in 880, East Francia also gained the western part of Middle Francia, including the mouths of the rivers Rhine, Maas and Scheldt and the cities Metz, Sedan, Strasbourg, Toul, Verdun, Cambrai and Antwerp.