CAMPAIGNERS for anti-monarchy group Republic will be protesting the Commonwealth Day service today at Westminster Abbey.

But what exactly is Commonwealth Day all about?

It marks the start of a week-long series of events and activities happening around the globe including faith and civic gatherings, debates, school assemblies and flag-raising ceremonies.

The service itself – starting at 2.15pm - has been held at Westminster Abbey since 1972, with the Commonwealth now in its 75th year.

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The event celebrates the “people and cultures” of the Commonwealth nations – an association of 54 member states from across the world.

Commonwealth Day is always marked on the second Monday in March.

A message has been recorded to mark Commonwealth Day by the King and will be played at the service. 

The theme for Commonwealth Day this year is  ‘One Resilient Common Future: Transforming our Common Wealth’, which will highlight how member states “must harness their strengths by building resilience, unlocking potential, leveraging the 'Commonwealth Advantage' and fostering a connected, digital Commonwealth.”

Is the Commonwealth still relevant?

The Commonwealth of Nations was formed in 1949 to maintain an association between countries that had once been part of the British colonies, but which were considered 'free and equal'.

But there remain questions over the continuing relevance of the Commonwealth given the vast majority of nations that are part of it are now republics.

While King Charles is the titular head of the Commonwealth, he is not head of state of republican members and holds no power within them. 

Only 15 member states have the British monarch as their head of state, while five have their own monarch and 36 are republics.

Several of the 15 members who still have King Charles as head of state have also expressed a desire to become republics in the near future including Australia and Jamaica.

Republic CEO Graham Smith said on Twitter/X: "Charles doesn’t serve the Commonwealth, the commonwealth serves a purpose for him."

The Republic protest will take place at United Nations Green, just outside Westminster Abbey, at noon.