William Dension

William Denison's grandfather was a Leeds woollen merchant, but his father went to London to make his fortune. Denison himself was born in the City in 1770, and pursued a banking career, ending up as senior partner of Denison, Heywood & Kennard in Lombard Street. His father had bought Yorkshire estates, including Seamer, near Scarborough from the Duke of Leeds for £100,000.

Denison, who was also a backbench MP for most of his life from 1796 onwards, died in 1849. His will was reckoned at the time to be worth £2.3m. The Yorkshire estates had risen to £500,000 in value and his land in Surrey some £100,000. The rest was in cash and securities. His fortune represented about 0.45% of net national income at the time, or £4.9bn in today's money.