Jeff,
Ron is right.
The wife of a King is a Queen.
You'd know her as The Queen Mother.
Memorial sites > HM Queen Elizabeth The Queen Mother

She was called Elizabeth too.
But as she wasn't the Monarch but the wife of the King she didn't get a number after her name.
As Elizabeth I and the present Queen , Elizabeth II were/are the Reigning Monarchs they get a number.
Well something like that.
I'm sure someone can explain it better than me.

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