I don't think it was used in Britain until the Hanoverian dynasty moved in - early eighteenth century, therefore. It gained momentum, became one of the names Jane Austen
used, and as far as I recall Dickens used it more for working-class women and children than for his (relatively) posh characters. Then it faded out, and now it's fading back in, along with Charlene
and Charlize and such.
I don't know when it came to prominence in Germany, and if it was a popular name before it became a royal one, but someone will - Satu
All the best