It was usually a short form of Anglo Saxon names Beorhtgifu meaning "bright gift" or Beorhtwynn meaning "bright joy".
The name occurs as a theonym, surviving as Berchta, a figure in Alpine folklore connected to the Wild Hunt, probably an epithet of *Frijjō in origin.
Bertha appears as a Frankish given name from as early as the 6th century.
This is notably the case with the mother of Charlemagne, Bertrada (properly berht-rada "bright counsel") called "Bertha Broadfoot."
In modern times, the name is associated with an unusually large example of a class of objects.