Anti-body snatching railings, 19th century England.
Evidently, iron railings around graves, one of which I found in a small Nicola Valley cemetery last summer, come from the era of 19th century body-snatchers and grave robbers in England. Freshly buried bodies were regularly dug up to sell to medical schools for dissection. Relatives would watch over the grave at night until the body had deteriorated to the point it was not worth digging up –two to three weeks.
This is all on the Jane Austen website, 19th century social practice arcana. So many traditions migrated to Canada leaving their particular histories behind: we are left with inexplicable material objects. In terms of fenced graves, it was the wealthy that could afford such a fiercely protective display. Where this occurred in the little Nicola Valley cemetery, there were two grand iron-fenced graves and then half a dozen less grand graves surrounded by wood picket fences.
The body-snatchers weren't in evidence here, but wealth was. Granite gravestones are shockingly expensive, if you've ever had to get one. They probably always were. Added to cast iron fencing, it was quite a display. I'm not sure that the dead are concerned with display, however the precision of a picket fence gives the dead some privacy and some propriety: a defence against obliteration.
St Michael's Cemetery, Nicola Valley, BC