Hi
My aim is to seek evidence of when the French removed French bodies from IWGC cemeteries. Let us first remember how they came to be buried there. All the examples I use are from Somme cemeteries but I have no reason to think the rules would be any different across the Western Front.
French burials can be divided into 3 groups.

Group1. When the British took over the Somme line from the French in July/August 1915 they also occupied the hospital sites and associated cemeteries which the French had been using. Post war all the French burials in these cemeteries were removed to French cemeteries with the notable exception of Louvencourt, where the 76 French burials there had been given impressive carved headstones. The sites left vacant were not reused.
Group 2. During the war a small number of French bodies were buried in Commonwealth cemeteries usually found during initial battlefield clearance. Post war the unidentified French burials were removed but the identified Frenchmen buried by the British were allowed to remain. The numbers were small, from all the work V Corps did between Serre and the Ancre there were only 2 identified Frenchmen, both are in Railway Hollow.

Group 3. Post War the battlefields were divided between the French and the British for the purposes of Clearance. The French cleared the area around Bray-sur-Somme and the British, with Canadian and Australian help, cleared the rest of the Somme area. The British were bound to find French bodies on the battlefield so the main solution was for the British to create a cemetery next to Serre Road 1 into which the French bodies found locally were buried and to create French Plots in 2 British cemeteries. These French plots are in Ovillers and AIF Grass lane, Flers. Like most international collaborative projects the principle is easily agreed at high level but the detail is corrected later. When the British buried Frenchmen in the 2 plots they buried identified and unidentified in individual graves with a cross for each. This is not the French way, the French later removed all the unidentified bodies to mass graves in French cemeteries leaving identified Frenchmen scattered within the French plot. They then exhumed some of the identified bodies and reburied them in the orderly plots we see today in the 2 cemeteries. To illustrate the size of this work there are now 168 Frenchmen in AIF where originally there were 416. The CWGC erroneously still uses, both on line and in the registerfor Ovillers
, the cemetery plan which shows many gaps in Rows K to Q of Plots 14 to 17. These gaps were originally French burials but are now occupied by Commonwealth burials.
There were a few French bodies buried in IWGC cemeteries during the clearances but any unidentified, as the 2 buried in Ancre, were removed. Queen’s Bucquoy received a group of French bodies previously buried by the Germans. The identified remain but the unidentified have been removed. The only 2 Unidentified Frenchmen in CWGC care are in London Extension. The reason they are still there is that they share a grave with an unknown Australian and I assume the remains were unable to be separated.

My question is-when did the removal work take place? Any evidence will be gratefully received.

Peter, that's a very interesting project you are working on, sorry I cant help you with your date query.

I'd always wondered why a French plot in a CWGC was a bit mish-mash. Now, with your post I can see how this may have come about.

Kind regards
Robert.

Nine Elms Military Cemetery, Thelus.