I found myself in Tower Hamlets cemetery in the East End of London, a couple of miles from work, a couple of miles from home. Who should I bump into there but Graeme, the man I first met mudlarking on the Thames foreshore. Graeme and I got talking, and went to his nearby house. There, he told me a story that I’m now going to tell you.

In the early Seventies, when Graeme and his then wife were in their twenties, he had a basement flat in Maclise Road, just behind Olympia in West Kensington. In the adjoining basement lived an elderly man, Henry Stevens, his bedridden wife and lots of cats. Graeme became friendly with this man. When the invalid wife died, Graeme and the widower became closer. “He called everyone ‘Mister’,” Graeme remembers.

After a while, the old man confided that he wasn’t really called Henry Stevens, that was merely the name painted on the side of a van he’d bought years before. His actual name was Constantine Imeretinski and he was a prince of the royal family of Georgia, a family that can trace its roots back to Alexander the Great. He had been born in the 400-room palace of Vichnevetz on his family’s estate in Poland (he showed Graeme a photograph), been educated in England and was a veteran of the Royal Flying Corps in the Great War. “He said, ‘Mister, we’d have to heave the bombs, 25lb bombs, out of the cockpit on to the German lines’,” Graeme recalls.

The Russian revolution of 1917, and the Bolsheviks’ subsequent invasion of Georgia, ruled out a return home for any aristocrats fortunate enough to be abroad. So Constantine had settled in Shepherd Market in Mayfair, living, Graeme surmised, a rather dissolute life for a while, but working too, as an engineer, at one stage becoming involved in the inter-war race to extract oil from coal. “He had an aptitude for mechanics,” says Graeme. “He was a little eccentric, but very sharp.”

Constantine showed Graeme some old share certificates (pre-revolution, obviously), but whatever usable money he had seems gradually to have seeped away. He moved to Chiswick, was bombed out of there in the Second World War, ended up in West Ken earning his living as a jobbing plumber. The prince, Graeme recalled, told this tale of plummeting social mobility with neither shame nor pride, embarrassment nor fanfare. Nor did his lineage dominate his conversation. It was simply one fact alongside other facts.

In the summer of 1978 Prince Constantine became frail. His personal hygiene, never the best, had declined. He would dole out cat food to his pets with a knife, then use the knife, unwashed, to butter his bread. One morning he told Graeme that he had dreamt overnight of being a boy again, in the palace in Poland, his mother calling him to join her. “I think he wanted to die,” says Graeme. “He was a big barrel of a man, maybe a bit of a tyrant in his day, but the post mortem said he was suffering from malnutrition.”

In November that year, Graeme took a cup of tea next door and found the old chap stretched out on the hall floor. Graeme made the necessary calls. The Prince had previously told Graeme he had family in France, and also introduced him to his niece (he had no children, was “without issue”, as the genealogists have it), a nice lady who was always grateful to Graeme for his sense of neighbourly duty. Some relatives came to collect the dead man’s memorabilia, stored in a trunk. Graeme and his wife went to the funeral, a small affair.

A few weeks later Graeme got a call from Roehampton crematorium, politely informing him that Henry Stevens’ ashes remained unclaimed and, ahem, a weekly charge was accruing. Graeme paid the arrears and took possession of the casket, informing the family, receiving no reply. Years passed. Graeme divorced, moved to East London, remarried, was widowed himself in 1993 at the age of 44. “I lost my job on the Friday and Cathy died on the Saturday,” he says. Shocked, redundant, grief-stricken, Graeme says he “didn’t open the curtains for three years”.

But then, as part of learning to face the world again, he decided to have a clear-out. This was perhaps ten years ago. He still had the wooden casket holding the remains of his neighbour from 20 years earlier. Taking an aluminium printer’s plate, Graeme inscribed it with his friend’s name and honorific, fetched a spade, and went around the corner to Tower Hamlets cemetery. The history of that cemetery says it opened in 1841 and the last interment took place there in 1966, but the second of those dates is not strictly true.

Graeme found a spot where some old graves had collapsed, forming a depression in the undergrowth. There he dug a shallow hole, placed the plate and casket inside, replaced the earth, the disturbance to be hidden soon enough in among the rampant nettles and brambles. Graeme straightened, remembered his friend for a moment, walked away. And thus was Prince Constantine Giorgievitch Imeretinski of the Royal House of Bagration-Imerati in the kingdom of Georgia laid to rest.

robert.crampton@thetimes.co.uk