Say the words "American gangster" and your mind invariably turns to criminals like Al Capone, Pretty Boy Floyd or John Dillinger. But one of the most successful of all gangsters - perhaps because he lived to a ripe old age - was actually a man of Welsh descent.

His real name was Llewellyn Morris Humphreys and for many years, under the assumed name or nickname of Murray the Hump, he was one of the most powerful men in the whole Chicago underworld.

Murray the Hump's parents came from Carno, a few miles outside Newtown, having been married in the Methodist chapel at Llanidloes. However, the final years of the nineteenth century were difficult for the small Welsh farming community and the young couple found it hard to make a living on their isolated hilltop farm.

As a result they decided to emigrate to America in the hope of "making it big" in the New World. Their son, Llewellyn Morris Humphreys, was born in their first American home on North Street, Chicago in the year 1899.

Conditions in Chicago were not much better than Carno and by the age of seven young Llewellyn had quit school and was making a living selling newspapers on the street corners. It was a rough and dangerous existence in a city where the newspaper sellers - and even the staff of the papers - fought with fists and baseball bats for the best pitches.

Luckily, Llewellyn found himself befriended by a local judge, Jack Murray, a man who took something of a benevolent and fatherly interest in the mischievous young boy.

He soon adopted the judge's name, Murray, instead of Llewellyn - which was probably just as well because nobody in Chicago could even begin to pronounce his real name anyway. And, of course, it let the other paper sellers know that he had powerful "protection."

Murray the Hump, as he became known because of his fondness for wearing fashionable camel-hair coats, quickly moved on, out of newspaper selling, into the world of gangsters and hit men. To begin with he worked as a hired gun - one of his early victims was apparently Capone's arch enemy Roger Touhy, blown apart by a shotgun blast shortly after his release from federal prison.

Forging his way up the ladder, Murray the Hump was one of the planners behind the infamous St Valentine's Day Massacre in 1929 when seven members of Bugsy Moran's gang were lined up against the wall of a garage in North Street, the very street where the Hump was born, and machine gunned to death. He was far too clever and too powerful to be involved in the killings himself but his was the hand that guided the machine gunners.

After that Murray the Hump was clearly destined for the top. He was the man who, when Prohibition was repealed in 1933, decided to channel the mobsters into the semi-respectable world of running bars, keeping saloons and distributing liquor.

He also became involved in controlling the unions and by the early 1950s the mob was making nearly $100,000 dollars a year under his careful and diligent management. The other interests of the mob, prostitution and gambling, the Hump kept to himself.

When Al Capone died in 1947 Murray the Hump succeeded him at the head of the organisation. The FBI were clear that the Hump was a violent and vicious gangster but one who always preferred to use his brain rather than the machine gun.

He was, they declared, the gangster who introduced money laundering to the mob, investing money from crooked deals in what were otherwise legitimate businesses. He was the man, they said, who was responsible for the introduction of gambling to Las Vegas.

Violence was, however, a way of life for Murray the Hump. It is believed that he murdered the husband of his mistresses, stabbing him with an ice pick before divorcing his own wife, a Native American by the name of Mary, and then marrying the younger mistress.

Murray the Hump never forgot his Welsh roots, so much so that he had a real desire to see what the country was like. He visited Wales just once, in 1963, travelling to the land of his parents under an assumed name. He never had the chance to come again as, two years later, at the age of 66, he died suddenly at his Chicago home.

It was perhaps just as well for the Welsh gangster as the FBI had just issued a warrant for his arrest and with his violent and murderous past beginning to catch up with him he was certainly looking at a long spell behind bars - or maybe even the death penalty.

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