6. 1957
We love this 1957 photo because it's just so glamorous — it's only natural the Queen would wear an outfit like that when meeting an American movie star. 

The American movie star with which she's chatting is Jayne Mansfield. She was in London to promote her film Will Success Spoil Rock Hunter?, which the Queen viewed at the Odeon Theater. Mansfield was a sex symbol of the late '50s and early '60s, and was groomed to be the next Marilyn Monroe. She was known for her love of publicity and her "wardrobe malfunctions," so we imagine it was a bit of a cultural clash (though, we're sure very cordial) when these two met.