The 4th Earl Cadogan

The Cadogan fortune stems from the exploits of William Cadogan, an Irish soldier who served in Marlborough's army with distinction in the battles against France in the early eighteenth century. By the end of the war, this Dublin lawyer's son was Colonel of the Coldstream Guards and an MP.

In 1716, he was created Baron Cadogan of Reading. His brother, who later inherited the title, made the family fortune by marrying one Mary Sloane in 1 71 7. She was the daughter and heir of Sir Hans Sloane, Lord of the Manor of Chelsea. That inheritance - now the 100 acres round Sloane Square - has become some of the most valuable real estate in the world. By the nineteenth century, the Cadogans' wealth had pushed them into the forefront of the British aristocracy. The 4th Earl, born in 1812, was not willing, however, to lead an idle life. He served in diplomatic posts in the key embassies of St Petersburg and Paris, and had been a Tory MP.

When he died in 1873, Cadogan left a relatively small will of around £80,000 in personal wealth. Yet the annual rental value of the Chelsea land around that time was £180,000 according to Professor Peter Lindert in an article entitled 'Who Owned Victorian England?' in the journal Agricultural History (1987). Cadogan's asset wealth would have been not far off 30 times the rental income - perhaps £4.8m, representing 0.44% of the then £1.075bn net national income. Today's equivalent would be £4.8bn.