Has England Ever Had A Queen Charlotte?

Yes, Britain indeed had Queen Charlotte who was wife of King George lll.  He reigned from 1760-1820.  Queen Charlotte lived from 1744-1818.
She was born Charlotte of Mecklenburg-Strelitz.  (George lll was actually a Hanoverian monarch).  The marriage was an arranged marriage, but there does seem to have been a happy relationship, as witnessed by their having 15 children together.
King George was often referred to as the Mad King, due to having the blood disease porphyria, which meant that he was not well for some considerable time and in 1810 blind and certainly deranged by his illness and the lack of treatment he had for it, he was contained within Windsor Castle as a prisoner, but Queen Charlotte is said to have been supportive of him throughout his illness and containment.  She died two years before George in 1818, when his condition was said to deteriorate even more.