Hugh McCalmont

An Ulsterman by birth, McCalmont made his money in nineteenth century London as a stockbroker and foreign merchant. He died unmarried in 1887, leaving £3.121m in his will to his great-nephew, who had to wait seven years before getting his hands on the money.

McCalmont's fortune represented 0.26% of the then £1.195bn net national income. Today's equivalent would be over £2.8 bn.