Vladimir Putin is fond of saying that borders can change. That is something the people of Poland and Ukraine know too well

My mother, Marie-Joséphine, knows what it is like to flee a Russian invasion of Ukraine. Nearly 82 years ago, aged 15, she escaped from the far south-western town of Kolomyia into Romania with her mother and twin sister. Her father had been imprisoned by the Russians in Lviv: she never saw him again. But my mother, now 97, is not Ukrainian. She is Polish by birth. When she fled her home in 1940, what is now western Ukraine was part of Poland, a nation which having regained its nationhood in 1918 after more than a century, was under occupation by Nazi Germany and Soviet Russia.

If my mother’s history appeared complicated – far more so than that of my English father – it was only when I accompanied her to the village near Kolomyia where she had been born that I discovered how many further layers of complexity there were. That was epitomised by an encounter with a 90-year-old woman who had looked after my mother and her twin sister when she herself was barely a teenager and my mother and her sister were toddlers, only ten years’ younger.

The twins and my grandmother had embarked on a refugee odyssey that took them to the southernmost tip of Africa before ending back in the northern hemisphere. My mother now finds herself widowed in the land of her husband’s birth. But her Ukrainian nursemaid, without ever leaving the village, had been a citizen successively of the Austro-Hungarian empire, Poland, the Soviet Union, and – finally – of an independent Ukraine.