Johann Theilinger was a Sudetan Czech from Mikulov.  He was baptised a Catholic and later in life could speak numerous languages. He fought in the International Brigades in Spain, the Czech army in exile, later joining No.10 Commando 3 troop aka 'X' troop. He served under the alias of John Taylor. Serious injuries after an accident with a phosphorous grenade at Littlehampton resulted in his discharge from active service.