Emaciated, tired and confused following a daring escape from a prisoner-of-war camp, soldier William Roberts faced the prospect of being shot as a German spy on his return home to Britain - and all because he spoke Welsh.After four years in captivity, Mr Roberts thought he had reached safety when he boarded a British ship heading to Glasgow after fleeing the camp in Poland.But once on British soil he was arrested as a suspected spy when he responded better to the Scottish authorities in German and Welsh than in English.His daughter, Mid and West Wales Assembly Member Joyce Watson, has spoken of her father's ordeal and claimed she was not taught Welsh as a child because of his experience.Mr Roberts died nearly 18 months ago and it is only now that Mrs Watson is learning more about her father's wartime exploits.Mr Roberts, a farm worker from Llanbrynmair, near Machynlleth, Powys, was aged 21 when he was called up to the Royal Welch Fusiliers in 1940.Joyce Watson AM (r) with her sister Irene Hansen and family friend Hedd Bleddyn Williams looking at old photos of Mr RobertsHe tried to converse with the Scottish authorities in bits of German and Welsh, but they couldn't understand himJoyce Watson AMThe first language Welsh speaker could speak very little English and received just three weeks' tuition before being sent to the frontline.It wasn't long before he was captured by the Germans at Dunkirk and became a prisoner-of-war (PoW).During his time as a prisoner he showed a flair for languages and learned Russian, Polish and German, and some French and Italian, said Mrs Watson.His knowledge of agriculture also landed him a job as a farm worker in a camp. The freedom this gave him led to his escape when he cut a hole through a fence one night, shortly before the end of the war.He was shot at and lost his big toe as a result, but eventually found a British ship which was setting sail for Scotland.Poor EnglishWhen the ship docked, his poor grasp of English marked him out as a threat and he was arrested as a spy when he was caught speaking Welsh.Mrs Watson said: "He tried to converse with the Scottish authorities in bits of German and Welsh, but they couldn't understand him."It was then that the authorities thought he was German and he was arrested."Fortunately, a Welshman was there when my father was arrested and he recognised the Welsh language and persuaded the authorities he wasn't a German spy."Mrs Watson added: "Just imagine what my father thought.He didn't want his sons to go through the same experience he had, so he spoke English to usJoyce Watson"He was seven stone in weight, he had been a PoW for more than four years, had escaped and travelled hundreds of miles and then faced the prospect of becoming a prisoner again in his own country."After the war when he became a father of four sons and four daughters, Mr Roberts' wartime experience led him to speak English at home because he did not want his children to go through the same thing."My father remained in the army after the war and like most people of his generation thought there would be another war, but this time with Russia," added Mrs Watson."He didn't want his sons to go through the same experience he had, so he spoke English to us."But Mrs Watson, Labour's rural affairs spokeswoman in the Welsh assembly, has since made a decision to learn Welsh.She has also seen, for the first time, some letters sent home by her father from his PoW camp.They were shown to her by a family friend Hedd Bleddyn Williams, from Llanbrynmair.