When Harry and Meghan, the Duke and Duchess of Sussex, announced their decision to step away as senior royals and strike out on their own, the British royal family joined the ranks of other royal families facing a changing reality. Months before Harry and Meghan reached their compromise with Queen Elizabeth II, the Swedish royal family had stripped certain family members of royal titles and cut them from the royal payroll. Meanwhile in Spain, members of the royal family have been removed from the succession after receiving prison sentences for corruption and tax fraud. And in Japan, the future of the royal family is in peril because of outdated succession laws that discriminate against its female members.

Forty-four of the world's 195 countries are monarchies. As a result of how the British Empire dissolved itself, 16 of these 44 have Queen Elizabeth II as their Head of State. With the exceptions of Saudi Arabia, Brunei, Oman, Eswatini, and the Vatican, all monarchies are constitutional monarchies, which means that the sovereign is a figurehead with limited political influence and power. During the 20th century, a newly created country could become either a republic or a monarchy. Israel, Lebanon, and Poland are examples of the former. Norway, Iraq, Saudi Arabia, and Spain are examples of the latter. At the same time, old monarchies became republics, often by force, with Cambodia bucking the trend and reinstating its monarchy in 1993. Two decades into the 21st century, the idea of a country declaring itself to be a monarchy seems almost alien. Has the monarchy as a system of government become obsolete?

The tradition of a royal person ruling a society can be traced at least as far back as the earliest state formations in the Middle East. During the 4th millennium BCE, the rulers of the Mesopotamian civilization of Sumer declared themselves kings and arranged for their sons to inherit their positions. Throughout the millennia that followed, monarchies reigned supreme as the preferred system of government, the Greek city states (except for Sparta), the Roman Republic, and the Commonwealth under Oliver Cromwell being a few notable exceptions to confirm the rule.

Monarchies as a system of government began to fall out of favor in Europe during the 18th century when the movement known as the Enlightenment put the age-old connection between religion, politics, and social hierarchies under scrutiny. Out of these debates grew the oldest and still-existing political ideology of liberalism.

Liberalism developed as a response to the absolutist monarchies that had dominated the European continent for the past few centuries. Absolutism describes a system of government based on a monarchy dominated and controlled by the sovereign. It developed from the 16th century onwards; it, too, in response to what came before, namely the monarchy of the Middle Ages where the sovereign's powers were counterbalanced by a council of nobles. King Louis XIV of France (1638–1715) perhaps described absolutism best when he quipped, "L'etat, c'est moi," or "I am the State."

According to liberalism, all citizens are equal with the right to self-government and self-expression. In a time dominated by absolutist monarchies ruling over vast cross-continental empires and supported by either the Catholic Church or a Protestant State Church, these claims proved to be explosive. The first liberal revolution was the American Revolution in 1776, soon followed by the French in 1789. Having rid themselves of George III and Louis XVI, respectively, the Americans and the French reconstituted themselves as republics, drawing inspiration from their forebears of Antiquity, the Greek city states, and Rome, and establishing a government for the people by the people without any religious influences. This is what we today call liberal democracy.

Together with the equally disruptive ideology of nationalism, liberalism piggybacked on the reach of the European empires across the globe and ignited independence movements and revolutions in places such as Haiti against the island's slave owners, the Philippines and Latin America against the Spanish, Africa and Asia against the French and the British. At the dawn of the 20th century, socialism joined the group of disruptive ideologies. The result was the toppling of even more monarchies, this time in Russia, China, and Ethiopia, just to name a few. The chaos created by World War I brought down the German, Austro-Hungarian, and Ottoman Empires, all of them almost exclusively replaced by either liberal or social-democratic republics.

As history demonstrates, monarchies and egalitarian-based societies are the anti-thesis of one another. Having a sovereign with total powers is incompatible with the people also having their say. From this inherent antagonism grew the system of government of the constitutional monarchy where the sovereign is stripped of all its powers but remains on the throne. The most drastic example of this change would be Japan, where Emperor Hirohito (1901–1989) went from being a near-divine absolute monarch to being a mortal figure head within the span of only a couple of years following the end of World War II.

The key to a monarchy's survival is its ability to adapt to the changes of the times. The monarchies that still exist have acknowledged this reality, whether it's the British monarchy letting Harry and Meghan go, or the Swedish monarchy acting preemptively to avoid a constitutional debate over its right to exist, or, indeed, the royals of Saudi Arabia allowing women to drive and get a passport without the permission of a male legal guardian. Because at the back of the mind of each king and queen, regardless of their powers being constitutional or absolute, lies the knowledge that in a world that is becoming increasingly democratic, there is always the option of a republic.

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