As the UK prepares for HM The Queen's Diamond Jubilee, I've started musing on which milestones various nations commemorate by issuing medals.

In the UK, it is the events relating to the Sovereign's reign: Coronations and Jubilees (along with a few state visits and Durbars, back when foreign travel, even if you happen to be a King, was a very big deal).

In Sweden, another constitutional monarchy, they have a different approach. The milestones they mark with a medal are very personal - significant birthdays of their monarch, weddings and wedding anniversaries... and even funerals. There's nothing about their monarch's connection with the nation. The award of such medals is also more personal: family members and people who organise or attend celebrations for whatever milestone is being marked being the only recipients.

Norway does both: there are birthday AND reign anniversary medals! Medals were issued to mark King Haakon VII's Coronation (1906), Silver Jubilee (1933), Gold Jubilee (1955) and his 70th birthday. Thailand too marks a mixture of State and personal milestones in their Royal Family's lives with the issue of medals - adding such occasions as the investiture of a Crown Prince to the expected coronations, jubilees and birthdays; along with one to mark 'The Longest Reign' in 1988.

As well as a fine memorial of Royal history, these series of medals give a fascinating insight as to the role of the monarchy in different countries around the world... and probably scope for a whole book not just a blog entry!