According to the family stories, my great-grandfather Moses Solomon landed in Cardiff as a boy at the end of the nineteenth century, escaping the pogroms of Lithuania. His name was not Solomon when he left his home country, but the immigration officer could not understand his eastern European accent and they chose the new name together. I was visiting Cardiff for the first time in May 2014 for a conference, and with Moses in mind felt I ought to go and look around the docks, though quite what I hoped to find I do not know. As I passed the great shiny glass-and-steel structure of the Welsh National Assembly, I noticed a rather peculiar little church with white slatted wooden sides and a grey roof. It was perched incongruously on the edge of the bay, as if it had perhaps just been dropped there temporarily. It reminded me of the innocent works of the Swedish painter Carl Larsson, which had adorned the walls of my childhood home.

I entered the café, which had taken over the ground floor of the church, and discovered that my instincts had been right. It was indeed a Scandinavian church, built originally as a temporary structure that could be moved if needed. It had been erected in the middle of the nineteenth century by the Norwegians as a seamen's mission; Cardiff had been a major port, and the Norwegian merchant fleet one of the largest in the world. With the decline in the shipping trade, the church had eventually closed, been dismantled and then resurrected nearby as the Norwegian Church Arts Centre.

‘You might like to see the exhibition space upstairs,’ the lady serving coffee suggested. I was due back at the conference but thought it would be impolite not to take a quick peek. As I climbed the narrow staircase, I looked up and got a shock. There, smiling down at me, was a picture of my old friend Roald Dahl.

What are you doing here? I thought. I soon discovered that the room I was entering was the Roald Dahl Gallery; he had been the first president of the trust that had restored the church. It all came back to me, then: Dahl's Norwegian father had landed here in Cardiff around the turn of the century, and set up a business supplying his compatriots working in the ship industry.