The title Head of The Commonwealth was created at the 1949 Commonwealth Conference as part of the formula to keep India in the association when it became a republic.
It was, as Vernon Bogdanor says, made specific to the King and was not specifically declared hereditary. But I would say that was the clear implication. Of course mischievous observers will try to encourage debate about this. Not least those in Australia who hope to use the succession as a reason for becoming a republic, rather than doing the hard work of demonstrating what is wrong with the constitution and how it would be improved by any change proposed.
When King George VI died in 1952, the Indian Prime Minister Jawaharlal Nehru, on behalf of the only Commonwealth republic at that time, sent Queen Elizabeth II a message welcoming her as Head of the Commonwealth. Her Majesty is thus Head by common consent.
I recall a colleague from Ghana arguing decades ago that the position should rotate around Commonwealth leaders. I was polite enough to not to point out that this could have included President Idi Amin or, later, President Mugabe. It is inconceivable that anyone, apart from the Sovereign of most of the Realms, could be Head of the Commonwealth.
The question has been raised with the report by Mark Reynolds in the Daily Express on 6 April 2007 that Prince Charles is to join the Queen at a Commonwealth Heads of Government Meeting in Uganda later this year. The newspaper says constitutional experts saw the move as a “highly significant” step for the Prince.
It also points out that it is extremely rare for both the monarch and the heir to the throne to be in the same overseas country simultaneously on official duties. The last time was 33 years ago for the 1974 Commonwealth Games in New Zealand. The Duchess of Cornwall will also be travelling to Kampala with the Prince, and the Duke of Edinburgh will accompany the Queen.
The Uganda meeting will also be attended by the Rwandan President Paul Kagame as an observer. According to Reuters on 16 February 2007, President Kagame hopes a bid by his country to join the Commonwealth will succeed, underlining a bitter rift with France.
"There are many benefits for us in joining the Commonwealth – cultural, economic, political. I hope they will then approve our membership. I am looking forward to it," he said.
Accession to the Commonwealth would be a clear snub to France after Rwanda severed diplomatic ties in November 2006. According to Reuters, President Kagame has had only bad words to say about France's record in Africa.
Rwanda is not the only applicant to the Commonwealth, an association some Australian republicans actually want us to leave or whose Games some wish us to abandon. This is not so surprising – their leaders in the nineties did not even bother to find out what happens when a country becomes a republic in the Commonwealth. (The evidence for the first two assertions can be found in the links inserted in the version of this column posted on the ACM site, and for the last assertion, in chapter 13 of The Cane Toad Republic).
Incidentally, the Commonwealth has appointed a team to consider six –yes, six – requests for membership from the Middle East and Africa. One day, I expect the United States to apply – it satisfies all of the criteria. After all, the Commonwealth is an international organisation which has standards. Membership means something.