Canada's place in the monarchy is one of the things that unites the country, says Gov. Gen. David Johnston.

Canada's "remarkable diversity" works because some things, like the monarchy, "holds us together," Johnston told CTV's Question Period.

Johnston says, over a thousand years, constitutional monarchies have evolved into a stable form of government.

"If you look at governments around the world and you want to identify those that are particularly stable and have served their people well, over the past 50, 100 years, Canada would stand up on the list and so would the three of the four Scandinavian countries have constitutional monarchies," he said.

"There's a stability that comes from that system of government where you have parliamentary democracy but you have a representative - a head of state, in our case the Queen, I'm her representative in Canada, whose responsibility is the constitutional law aspect and reinforcing the fundamental values of the country, and ensuring that rule of law and stability of law persists and consists."

Johnston will be arriving in England on June 9, to take part in 90th birthday celebrations for Queen Elizabeth II. The following day will include church services at Saint Paul's Cathedral and a lunch hosted by the Queen for the 15 governors general in the Commonwealth realm. June 11 will bring the trooping of the colour, an event of great pageantry, says Johnston.

"The Brits do that very well."

The trooping of the colours is a ceremony performed by the regiments of the British and Commonwealth armies and has been used to mark the British sovereign's birthday since 1748.