These photographs are from an old cemetery on the East-bound road to Dugald, Manitoba, in an area with Eastern European ancestry. I photographed them one sunny March day in 1980 where I discovered this tradition for the first time.
It is interesting to compare the above with this unique plaque found in a small Newfoundland cemetery near McIvors. It is odd in that is not of the living person, but of his corpse. There are no other photo-plaques in this cemetery (yet).
A permanent likeness of the deceased on their last resting place has been a long-standing tradition, as illustrated this Mummy portrait of a young woman, 2nd century, Louvre, Paris. (...and let's not forget Tutankhamen.)
This tradition was also seen in the 17th Century as well. See Wikipedia's entry which includes this coffin portrait (right) of Barbara Domicela Lubomirska née Szczawinska, 1676. Oil on tin plate. Current location is the National Museum in Warsaw, Poland. It became a tradition to decorate coffins of deceased nobles (szlachta) with such funerary art in the times of the Polish-Lithuanian Commonwealth, particularly in the 17th and 18th centuries, the time of the baroque in Poland and Sarmatism. This tradition was virtually unknown outside the Commonwealth.
In Italy we found along with 20th C photo-plaques beautiful 19th C bas relief portrait sculptures. Most are very accomplished, as one would expect in this land of great marble sculpture. Some of these images are from Cortona in Tuscany, others from de Cementerio de San Michele in Isola near Venice.