The Spencers have been king makers since they loaned Henry VIII money to keep his court running. Each king since then has had money loaned to them by the Spencers, who were only, after all, merchants. But merchants with money.
In the 1700s the Spencers were awarded the title of Earl, and a house to go with the title. The only man who didn't become king was Bonny Prince Charlie, whose profligate ways were not approved of by Earl Spencer. Princess Diana left her legacy to The Royals, too - along with money - The Heir and The Spare.