The usual answer is Mary I of England , often called “Bloody Mary,” who was the first woman to rule England fully in her own right as queen regnant (from 1553 to 1558).

However, there are a couple of important nuances people discuss:

  • Some historians point to Empress Matilda in the 12th century as the first woman who claimed and briefly held royal power in England, though her rule was heavily disputed and led to civil war, so she is not always counted in simple “quiz-style” answers.
  • A few modern commentators argue about other “firsts” (like earlier queen consorts or later legal interpretations of queenship), but when people ask “who was the first queen of England,” they almost always mean the first undisputed reigning queen, which is Mary I.

So, for a quick scoop-style answer:

  • First undisputed queen regnant of England: Mary I (Bloody Mary).
  • Earlier but contested female ruler sometimes cited: Empress Matilda.

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