The American Virginia Hall and her wartime service with SOE is well known but Robert Byerly is less well documented and is sometimes wrongly described as a Canadian.
When Germany invaded France in April 1940 Robert Byerly who has been noted for being pro-British was living in Paris and because he was a citizen of a neutral country was allowed to leave France and made his way to England and in 1941 enlisted into the Canadian Army and trained as a signaller. The date he was recruited by SOE and passed selection varies according to sources, but it is known he arrived in France by parachute on 8 February 1944 near Poitiers to work as the wireless operator for SURVEYOR circuit. His infiltration was arranged by PHONO circuit but unknown to London the circuit had been infiltrated and Byerley along with two other agents were dropped to waiting German soldiers.
Under German supervision Byerly was forced to use his wireless to contact London and within the body of the message inserted a ‘bluff check’ and left out the ‘true check’ to warn London he was sending under duress. As was standard practice London maintained contact with Byerly to create the illusion he was of use to the Germans and hope he would not be executed, but his transmissions suddenly stopped, and was not heard again. After the war it was discovered that sometime during the summer of 1944 Robert Byerly was transported to Gross-Rosen concentration camp where he was executed a few days later.