In a memoir published in 1998, journalist Trevor Grundy recalled how, when he was a boy just after the war, his mother used to come out on to the front step of their house in Paddington to see him off to school. As he turned out of the square where they lived, he’d wave back at her.

Each morning, she’d stand to attention and fling out her right arm in a full fascist salute. ‘I returned it. “PJ,” she shouted – Mosley-follower speak for “Perish Judah”. I shouted it back.’ And then he’d run, satchel flying, to catch his bus.

A decade earlier, in Sussex, a little girl called Diana Bailey had been taught to greet people in the same way. Her parents, too, were supporters of Sir Oswald Mosley. Those who knew him always speak of Mosley’s remarkable charisma. Muscular (he was a keen fencer), with a characteristically upright bearing, he was a life-long womaniser, with a dash of the swashbuckler about him.

Bailey’s parents instructed her to use the straight-arm salute and to say ‘PJ’ to passers-by when they went for an afternoon stroll. Sometimes people responded in kind: the Bognor Regis area had an especially active branch of Mosley supporters.