He came to Britain as an immigrant, fought his way to the top and could not have made it without the help of steel.

But the richest-ever man in Britain is not Lakshmi Mittal, the steel tycoon who was born in India and has topped The Sunday Times Rich List three years in a row with a fortune now worth £19.25 billion.

No, Alan Rufus came from Brittany in northern France. At today’s values his fortune is estimated to be worth more than £81 billion – three times the wealth of Bill Gates, the co-founder of Microsoft, and enough to buy Roman Abramovich’s Chelsea team 300 times over. But Rufus, or Alan “the Red”, can never spend it. He died more than 900 years ago.

He heads a list of 250 people in a new book, The Richest of the Rich, by Philip Beresford, who compiles the Rich List, and Bill Rubinstein, a professor of history at Aberystwyth University. The list excludes monarchs.

Their study stretches back to the Norman conquest of 1066 and includes medieval barons, moneylenders and monks as well as modern-day billionaires. Mittal just scrapes into the top 20 at number 20; Abramovich is at number 59 with £10.8 billion, a few ducats behind Cardinal Thomas Wolsey, builder of Hampton Court Palace, who was worth just over £11 billion.

Even through the ages there is a north-south divide. Of those on the list, 136 lived in London and the southeast while only 36 lived in the north.

Rufus, a Breton warrior who joined the invasion led by his uncle William the Conqueror, probably did more than anyone to start the divide in the first place. He led the vicious “harrying of the north”, a brutal suppression of rebellion that led to the loss of 150,000 lives and reportedly reduced the survivors to cannibalism.

When he died at 53 in 1093 he had a fortune of £11,000. Beresford and Rubinstein, using figures from probate records and ancient documents, calculate that the sum represented more than 7% of the net national income of the time. With an equivalent percentage today, Rufus would be worth £81.33 billion, making him easily the richest Briton of all time.

Rufus was once accused of abducting Gunhilda, daughter of King Harold, from a convent and seducing her. But he left no children and his estates passed to his brothers. His legacy is Richmond Castle, above the River Swale in North Yorkshire, which he began building in 1071.

Life was as comfortable as it could be for anyone in the 11th century.

“The central heating was a brazier in the hall, there was water from a reliable well and the garde-robes – the toilets – are still in good condition today,” said Lorraine Cooper, custodian of the castle for English Heritage. “He would have had fantastic views from his private apartments.”

Everything and everybody he saw, he owned.

William had given Rufus vast tracts of land as a reward; in all he owned 250,000 acres in Yorkshire, Norfolk, Suffolk, Cambridgeshire, Northamptonshire and London. David Morris, author of The Honour of Richmond, a history of the estate, said: “The closest person to him today would be the Duke of Westminster with his property empire.”

Rubinstein said: “The Norman conquest was probably the biggest hostile takeover of all time.

The people who helped William were handsomely rewarded.”

Four of the top six in the list were Norman barons. It also includes medieval “celebrities” such as Edward, the Black Prince, worth almost £35 billion, and Thomas Becket, who despite his saintly image had built up more than £24 billion in today’s money before he was murdered in Canterbury Cathedral in 1170.

The highest ranking woman is Eleanor of Aquitaine, wife of Henry II, at number 62 with a fortune estimated at just under £10 billion in today’s terms. Eleanor, played by Glenn Close in the most recent screen version of The Lion In Winter, lived to the grand age of 82.

“Nobody is likely to be as rich as Alan Rufus again but today wealth is far more democratic,” said Beresford. “It is also safer to be rich now. Rufus was lucky enough to die in bed, but of the 250 on the list 29 were either executed or met a violent death.”

Click here to view the top 250 richest people ever

Source: The Richest of the Rich by Philip Beresford and William D Rubinstein published by Harriman House October 15

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