In England the usual medieval term was churchyard. But at that time it was basically an open space, usable for other purposes. The gentry were inside the church, and the plebs couldn't afford permanent memorials. Coffins weren't buried - they'd want the remains to disappear before they re-used the same spot for somebody else.
Quakers started burial grounds in the 17th century. They thought memorials were too pretentious.
Things changed in the 18th century, when the better-off plebs could afford headstones. The churchyards started to fill up, and eventually they'd have to think about allocating more land, which might not be adjacent to the church. Spaces full of permanent graves were now a feature of the landscape, and the word graveyard seems to have entered the language in that era.
The word cemetery wasn't used much until the mid-19th century, when local bigwigs were authorized to set up committees to run public cemeteries. There were a few commercial cemeteries before that.
Nowadays the word graveyard is atmospheric - it mostly seems to be used with word like disused, overgrown or derelict. Or something spooky.