There was a Grenadier Guards Bandsman that wore his entitled Iron Cross, he is mentioned somewhere in the annals of ARRSEA lead contender for the most famed Royal Pioneer Corps soldier would have to be;
Capt Herbert Sulzbach OBE, Iron Cross 1st & 2nd Class
A decorated WW1 German artillery officer who wrote the classic 'With the German Guns', Capt Sulzbach had to flee Germany because he was Jewish.
After being interned on the Isle of Man, he volunteered for the Royal Pioneer Corps and
became an interpreter.
He became well known for his work in German POW Camps for his re-education of many former Nazis, winning them over to the idea of democracy, prior to their repatriation; and also for his post-war efforts to reconcile the former enemy nations.
One account of him reads:
Many of the several thousand officers who passed through Sulzbach’s hands
recorded moving tributes to his achievements in re-educating them towards
democracy. In 1982 they laid a plaque at the camp's site, making special mention of
‘Captain Herbert Sulzbach O.B.E. who dedicated himself to making this camp a
seedbed of British-German reconciliation’.
There's a fair bit about him on the internet but this article from the Jewish Chronicle paints a good account.
Featherstone Park Camp
Here's his medal collection but I've seen no evidence that he ever wore his German military decorations on his British uniform.
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