When war broke out his father was captured in Soviet-controlled Poland and murdered in the 1940 Katyń Massacre.
At the end of the war Świerczkowski's mother was forced into hiding near Toruń until she was confident that she could win exoneration from the Soviet-controlled government for her Volksliste status and be rehabilitated as a Polish citizen.
He graduated with a PhD in 1960, his dissertation including the now-famous three-gap theorem, which he proved in 1956 in answer to a question of Hugo Steinhaus.
He was allowed abroad from Poland to study at Dundee University, where his work with Alexander Murray MacBeath would later attract the attention of André Weil.
When the Polish Academy of Sciences granted him a passport to attend a conference in Stuttgart he used this as an opportunity to leave Poland for good in 1961, first resuming his fellowship in Glasgow before taking a job in the recently created University of Sussex.
In 1973 he left mathematics, moved to the Netherlands and built a yacht in which he sailed around the world for ten years.