Queen Elizabeth II holds many titles, including the longest-serving female head of state and longest-reigning monarch, but there is one title that has continued to evade her: Empress. However, it may be possible for her to also obtain that distinction in the future.

According to Express, there has only been one British royal who has ever secured the title of Emperor or Empress, Queen Victoria. In May 1876, she was given the special name of Empress of India after discussions with Benjamin Disraeli, who was serving as prime minister at the time. She then used the title from 1876 to 1947, which is when the British rule over India ended.

An emperor or empress is defined as someone who is "widely regarded as the highest ranking Monarchical title." In contrast, a King or Queen is someone who governs over a kingdom. At this time, the only empire left in the world is in Japan, which is ruled by Emperor Akihito.

The title of Emperor originated in the Roman Empire, according to Royal Central, and monarchs have since attempted to use it "due to the positive connotations that are associated with the massive land control and power of an Emperor."

However, doing so may also come with certain negative associations as the term has also long been associated with imperialist agendas and tightening controls. Therefore, it is viewed a bit more negatively than King or Queen.

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As reported by Latin Times, in 1801, there was a proposition to call Britain the United Empire of Great Britain. King George III ultimately rejected this proposal because he said that only kings and queens should exist within Britain, not emporers and empresses.

Per Express, there is nothing theoretically that could prevent Queen Elizabeth II or other future British royals from calling themselves the name, but it seems highly unlikely that if she decided that the name suited her it would be permitted.