Britain has only had six queens and only five without co-rulers as Mary II ruled with her husband William of Orange. Victoria, Anne and Elizabeth II have had fairly moderate rules in terms of the power they have exerted since the Glorious Revolution ensured the monarch doesn't have too much control through the Bill of Rights. Queen Mary I ruled for a relatively short amount of time and as a Catholic, she took part in things like burning Protestants which made her very hated. Elizabeth I (her sister) had a very long rule defeating the Spanish Armada and beginning a period of British imperialism (Virginia which was the first of the 13 colonies named after her) as well as exploration (e.g. Francis Drake) so she had an extremely successful rule. Anne had some significance as she helped orchestrate the Act of Union 1707 combing the Scottish and English thrones creating Great Britain. Of course Victoria's reign saw the greatest levels of imperial expansion but by then she was leading very little of it and most of the expansion was being led by parliament and the government. Elizabeth II is our longest reigning monarch and she did help facilitate the decolonisation process which took several decades and has been a great Head of State and ambassador for the United Kingdom.

Like kings, they governed through councils that were until the 20th century exclusively male. That isn't to say that the Queen lacked power over her advisers - until the 18th century they could be overruled or dismissed (or worse), and often were. But the machinery of government went on as before. The greatest upheaval probably followed the arrival and departure of Mary, each occasioning a reversal of religious policy emanating from the monarch herself. The two Elizabeths and Victoria regularly top "greatest monarch" polls.