I think one would have a difficult time finding an American or a Brit who hasn't tasted Earl Grey tea in their lifetime, but it's one of those teas that you either love or loathe. Personally, I love it. There are - dare I say - hundreds of makers of the tea known as Earl Grey*. My favorite Earl Grey tea is made by Darvilles of Windsor.
My stash of Darvilles Earl Grey
So who was Charles Grey and why was a tea named after him? I'm glad you asked! Charles Grey was a British Whig statesman and eventually, a Prime Minister (the abolition of slavery in the British Empire occured during his tenure).
Grey the politician was a model statesman, but Grey the man was a notorious philanderer both before and after his marriage to Mary Elizabeth Ponsonby. If you saw the brilliant film The Duchess (starring Ralph Fiennes and Keira Knightley) you would have learned that Grey's first and most "politically significant conquest" was his pursuit of the lovely Georgiana Cavendish, the Duchess of Devonshire. She later bore him a child, Eliza, who curiously was brought up by Grey's parents as though she was his sister.
There are several theories on how a tea came to be named after him but the most logical one is that a sample or gift of a flavored tea was given to the then Prime Minister Grey, he liked it, and when he ran out of it, asked for it to be copied. Twinings (tea merchants since 1706 and still located in their original wee shop on the Strand in London) claims that the Earl asked them to copy the tea and that from then on it became known as Earl Grey's tea.
* Each tea vendor has their own "recipe" for Earl Grey and there are a lot of varieties out there, but a true Earl Grey tea should be blended from a black China tea and scented only with natural oil of bergamot, an oil extracted from the rind of the bergamot orange, a fragrant citrus fruit. Nothing more, nothing less. Earl Grey tea is also used quite successfully in cake, cookie, ice cream, and drinks recipes.