Wikipedia
Fredegund (or Fredegunda) ( Latin: Fredegundis; French: Frédégonde) (died 597) was the Queen consort of Chilperic I, the Merovingian Frankish king of Soissons.
Fredegund was born into a low-ranking family but gained power through her association with King Chilperic. Originally a servant of Chilperic's first wife Audovera, Fredegund won Chilperic's affection and persuaded him to put Audovera in a convent and divorce her. Gregory of Tours remarks that Fredegund brought with her a handsome dowry, incurring the immediate affection of King Chilperic. But Chilperic then put Fredegund aside and married Galswintha. Galswintha died the same year, probably strangled by Fredegund(c. 568), who succeeded Galswintha as queen. Galswintha's sister, Brunhilda, however, began a feud which lasted more than 40 years.