Meghan Markle may not be a member of the royal family yet but she joined the Queen and senior royals for one of the most important events of the monarch's year - the Commonwealth Day service.
The US actress' attendance at the Westminster Abbey service marks a major milestone for Prince Harry's bride-to-be, as it the first time she has taken part in an official event with the Queen.
Celebrated across the Commonwealth, the day is an opportunity for each of the institution's 53 member states to highlight the positive values of the family of nations.
In her Commonwealth Day message, which is printed in the event's order of service, the Queen praised the "Commonwealth connection" that allows people from different nations to bond and celebrate "diversity".
London will soon host a gathering of leaders from the family of nations and the Queen, who is head of the Commonwealth, also paid tribute to the biennial event as an example of how consensus can "help to create a future that is fairer, more secure, more prosperous and sustainable".
With the UK leaving the European Union the importance of the Commonwealth may increase according to some commentators.
Members of the royal family arrived ahead of the Queen including the Prince of Wales, Duchess of Cornwall, Duke of York and Princess Royal as did the Prime Minister Theresa May
Screams and shouts from the public greeted Meghan and Harry when they arrived and the American actress looked stylish in a dress and coat by Amanda Wakeley and hat by Stephen Jones.
The Duchess of Cambridge, who was joined by the Duke, wore a dress and coat by Beulah and hat by Lock and Co.
The Commonwealth has played an important role throughout the Queen's reign, and she takes a special interest in the family of nations.
Harry and Meghan signalled their commitment to the Commonwealth and its people when they both mentioned the institution - which has the Queen as its head - during an interview to mark their engagement.
The prince said they looked forward to travelling around the Commonwealth, meeting some of the 2.4 billion people from the 53 member states.
Human rights campaigner Peter Tatchell led a noisy protest across the road from the Abbey where activists banged drums and chanted slogans as they called for greater rights for the LGBT community in Commonwealth countries.
Mr Tatchell appealed to the Queen's grandsons and their partners to make their voices heard on the subject, claiming 37 Commonwealth countries criminalise homosexuality, nine others have life imprisonment and in parts of two countries there is even the death penalty for gay people.
He said: "We hope the younger royals like William, Catherine, Harry and Meghan will recognise the immense persecution suffered by LGBT people in the Commonwealth and speak out as they have on many social issues."