The Franks were a confederation of West Germanic tribes that lived in the 3rd century north and east of the Lower Rhine. Under the Merovingian dynasty, they founded one of the Germanic monarchies which replaced the Western Roman Empire from the 5th century. The Frankish state consolidated its hold over large parts of western Europe by the end of the eighth century under Charlemagne.
In the 3rd century AD, the Franks tribes included the Salian, Ripuarian, Sicambri, Chamavi, Bruteri, Chati, Chatuari, and Batavians. They inhabited the lower Rhine valley and lands immediately to its east. In 358 AD, the Salian Franks poured over the Rhine into the Roman Empire, but they were accepted as an associate or allied people by emperor Julian the Apostate. By the end of the 5th century, with the fall of the Roman Empire, the Salian Franks extended their footprint on Roman soil to a territory including the Netherlands south and west of the Rhine, Belgium and Northern Gaul (northern France), where they encountered other peoples also of the Frankish ethnicity. Allied to the Romans, the Salian Franks fought alongside the Roman legions under the command of Flavius Aetius against the Huns at the Battle of Catalaunian Plains where Atila was thoroughly defeated.
The Salian Franks gave rise to the Merovingian dynasty with Clovis I, who proclaimed himself as King of the Franks, uniting all the Frankish tribes under one ruler. He conquered the Kingdom of Soissons of the Roman general Syagrius and expelled the Visigoths from southern Gaul at the Battle of Vouille, thus establishing Frankish hegemony over most of Gaul, excluding Burgundy, Provence, and Brittany, which he left to his successors, the Merovingians, to conquer.