I'm no scholar or history buff but a quick Google search for Merovingian brings up this site: https://merovingiandynasty.com/origins/

Just some interesting tidbits...

--9th century B.C. Scythia

This was an area of Eurasia that included the Caucasians including Azerbaijan, the central Asia steppes including Uzbekistan, Turkmenistan, Tajikistan, and Afghanistan, the valley of the Indus or that area between India and Pakistan, and the southern Ukraine with the lower Danube and Bulgaria.

A 2500 year old mummy was recently found in the snow capped mountains of Mongolia with blond hair, tattoos, and weaponry.

Carbon 14 dating has allowed archaeologists to trace the emergence of the Scythians to the Sayan-Altay mountains from 3000BC to about 500BC. These mountains are where Russia, China, Mongolia, and Kazakhstan come together. They are also known as the homeland of the Turks.

About 900 BC the Scythians began a western migration. They were nomadic warriors who rode horses bareback and who used archers, and the women fought along side the men.

They were described as long haired warriors who were ferocious. Edmund Spenser wrote that the primary nation that settled Ireland were the Scythians , and that they also settled Scotland.

--7th century B.C. Cimmerians

The Cimmerians in 714 BC were in the region of Azerbaijan, and in the 7 and 8th century BC were in southern Russia and Ukraine. Their language was Iranian.

There were many off shoots of the Cimmerians. Numerous Celtic and Germanic peoples descended from the Cimmerians. The etymology of Wales is said to descend from the Cimmerians. The Celts in France were known as Gauls.

--1st century B.C. Sicambri

The Sicambri were located along the right bank of the Rhine and appear about 55 BC. They fought several wars with Rome, namely one led by Gaius Julius Caesar. In 16 BC they defeated the Roman army under Marcus Lollius. About 11 BC they were forced to move to the left side of the Rhine by Nero Claudius Drusus.

The Merovingians claimed their descent from the Sicambri, who they believed were originally a Scythian or Cimmerian tribe once inhabiting the river Danube that changed their name to the Franks in 11 BC under the leadership of a chieftain called "Frankus".

--3rd Century A. D. Franks

Merovingians There were two groups of Franks-the Salian Franks and the Ripuarian Franks. The Salian Franks (sea dwelling) lived North and East of Limes in the Dutch coastal area and in the 5th century migrated throughout Belgium and into northern France. By the 4th and 5th centuries, the Belgium city of Tournai had become the center of activity. The Ripuarian Franks (river dwelling) lived along the Rhine river, and were perhaps called Ripuarian by the Romans. By the 9th century any differences between these two groups had disappeared.

They were involved with the Romans as military recruits in the 5th century. Gregory of Tours, the historian, placed the emergence of the Merovingians at the conclusion of the Frankish migration. The Liber Historiae Francorum went further, connecting them with the Trojan migration. Gregory of Tours wrote that the Franks had created long haired kings in Thuringia (Belgium).