I stumbled onto this site today: The Commonwealth War Graves Commission (CWCG )
This is the description found on the welcome page: “‘Debt of Honour Register’ is the Commission’s database listing the 1.7 million men and women of the Commonwealth forces who died during the two world wars and the 23,000 cemeteries, memorials and other locations worldwide where they are commemorated.”
I don’t know how long they have been around but searching for people who were casualties with Nationality of South Africa, produced 21382 hits! *There is a note though that the nationality does not mean they were South African, but that they fought and served in South African troops or units. I was quite excited. I’m not aware of any relatives that were casualties in any World War I or II, but I’m sure there are many researchers out there who will find this site very useful.
Click here to SEARCH