Labour MP Dame Margaret Hodge took a close personal interest in a Ben Uri Gallery exhibition at the 12 Star Gallery in Westminster which she visited last week.

Looking at the painting of Wilhelm Hollitscher at the show, Art-Exit 1939 — A Very Different Europe, she exclaimed: “It is my old grandad… how amazing.”

The Labour MP had been unaware of the portrait of her grandfather — an engineer who fled Austria in the late 1930s — until one of her sisters saw it and recognised him. Mr Hollitscher’s wife, Marianne, was a Holocaust victim.

“We’ve got photographs of her, [she] is really so beautiful,” Dame Margaret told the Guardian. “She was 55 and she thought they wouldn’t touch people who were really old.

“The last thing is she is taken to a camp in Lithuania and she was shot. We’ve got the last letter she wrote to my uncle. It is so poignant. She says twice in it: ‘Don’t forget me completely.’”

Despite being in his 60s and in poor health, Mr Hollitscher was interned in Liverpool as an “enemy alien” shortly after arriving in the UK.

In the Huyton camp, he was painted by the distinguished artist, Hugo Dachinger, a fellow Austrian.

Mr Hollitscher’s diaries revealed that he loved music and politics but was unhappy in the UK. Not speaking the language, he felt isolated and depressed. He died in 1943.

Ben Uri executive chair David Glasser said Dame Magaret’s visit was “extraordinary to be a part of. Just imagine getting to see your grandfather again in that context. She was visibly excited and it was as poignant as it was exciting.

“This is what Ben Uri is all about — enabling connections. We tell the story not only of the artist but of the moment and what was happening in history at that time.”