It does seem hard to find information about these on the Internet. What I have come up with so far, is that they were made in England. They would appear to represent works of painted art by prominent artists.
There are some similar items listed on the following link, if you would like to see them. eBay Express: 4 ANTIQUE BRASS PLATES/PLAQUES- MADE IN ENGLAND-NR!!! - Description
Hopefully, the link that I gave will still be working for someone to click on it.
That is at lease one answer for you. I will keep looking. Hopefully, others will also be along to add the things that they have found.