Excerpts from Books and Wikipedia
"The Merovingian dynasty was the ruling family of the Franks from the middle of the 5th century until 751. . . . By 509 they had united all the Franks and northern Gaulish Romans under their rule. They conquered most of Gaul, defeating the Visigoths (507) and the Burgundians (534), and also extended their rule into Raetia (537). In Germania, the Alemanni, Bavarii and Saxons accepted their lordship. The Merovingian realm was the largest and most powerful of the states of western Europe following the fall of the Western Roman Empire. . . . The first known Merovingian king was Childeric I (died 481). His son Clovis I (died 511) converted to Christianity, united the Franks and conquered most of Gaul. . . . During the final century of Merovingian rule, the kings were increasingly pushed into a ceremonial role. Actual power was increasingly in the hands of the mayor of the palace, the highest-ranking official under the king. . . . When King Theuderic III died in 737, the mayor Charles Martel continued to rule the kingdoms without a king until his death in 741." [Wikipedia]