King Charles has officially been crowned at his historic Coronation ceremony alongside his wife Queen Camilla.
At midday the Archbishop of Canterbury Justin Welby placed St Edward's Crown upon Charles' anointed head during the historical service at Westminster Abbey.
The King prayed to be a "blessing" to people of "every faith and conviction".
He became the 40th reigning sovereign to be crowned at the Abbey, the nation's coronation church since 1066.
The archbishop adjusted the weighty crown for several seconds on top of the monarch's head.
The historic moment, watched around the globe, was a fulfilment of the King's destiny, but followed the death of his mother, Queen Elizabeth II, last September after a 70-year reign.
It prompted a fanfare, the Abbey bells to ring out as well as a Gun Salute fired by The King's Troop Royal Horse Artillery stationed at Horse Guards Parade.
Several arrests were made prior to the event, including protesters wearing T-shirts saying 'Not my King'.
The crown was made from King Charles II in 1661 as a replacement for the original medieval crown that was melted in 1649.
However, it follows the original in having four crosses-pattée and four fleurs-de-lis, and two arches.
The crown is topped with an orb and a cross, symbolising the Christian world, and is made up of a solid gold frame set with rubies, amethysts, sapphires, garnet, topazes and tourmalines.
It has a velvet cap with an ermine band.
St Edward’s Crown was worn by Queen Elizabeth II at the Coronation in 1953.
Soon after her husband, Camilla had her own special moment when Queen Mary's crown was placed on her anointed head by the Archbishop.
Ahead of the Coronation, minor changes and additions were made to the crown such as the inclusion of the Cullinan III, IV and V diamonds which were part of the late Queen's personal jewellery collection for many years.
There was a touching moment between the King and Prince of Wales as William paid homage, the only blood prince to do so, in a break with tradition.
William appeared to avoid eye contact with his father through much of the homage.
He then kissed Charles on the cheek and the King was seen to say a few words to his elder son.
Prince Harry, meanwhile, was seen in the television footage watching intently as the archbishop raised the crown above his father's head before crowning him.
And when a few minutes later the congregation paid homage to the new monarch, Harry was seen, along with the other royals around him, speaking the words: "God save King Charles. Long live King Charles. May the King live forever."
Earlier, the royal couple left Buckingham Palace in the Diamond Jubilee State Coach after spending the night at Clarence House and headed along the procession route to the Abbey to be crowned.
The pair waved to the crowds as they passed by in the coach, with the route lined with thousands of wellwishers and military personnel.
The coronation was a deeply religious ceremony steeped in symbolism and its prayers took the theme of "Called to Serve", an attribute associated with the late Queen who pledged her life to the Commonwealth.
Before the crowning the archbishop delivered a sermon to the 2,300 guests, a gathering of world leaders, celebrities, UK politicians, foreign royalty, everyday heroes and the royal family.
Mr Welby began by telling the congregation: "We are here to crown a King, and we crown a King to serve.
"What is given today is for the gain of all. For Jesus Christ announced a kingdom in which the poor and oppressed are freed from chains of injustice. The blind see. The bruised and broken-hearted are healed."
Speaking to Charles and Camilla, Mr Welby said: "The weight of the task given you today, Your Majesties, is only bearable by the spirit of God, who gives us the strength to give our lives to others.
"With the anointing of the Holy Spirit, the King is given freely what no ruler can ever attain through will, or politics, or war, or tyranny: the Holy Spirit draws us to love in action."
Charles delivered a King's Prayer, the first time a monarch has spoken words to God aloud during a coronation, and he touched on the duty of the sovereign to serve all communities.
He told the abbey: "God of compassion and mercy whose son was sent not to be served but to serve, give grace that I may find in thy service perfect freedom and in that freedom knowledge of thy truth.
"Grant that I may be a blessing to all thy children, of every faith and conviction, that together we may discover the ways of gentleness and be led into the paths of peace.
"Through Jesus Christ our Lord, amen."
In the stillness of the abbey, Mr Welby held St Edward's Crown high above Charles and, placing it on his head, said "God save the King" - words repeated by the congregation.
The coronation ceremony ended at 1pm and the newly crowned King and Queen began the procession back to Buckingham Palace in the gold state coach.
Some 4,000 sailors, soldiers, aviators and other military personnel from across the UK and the Commonwealth will accompany Charles and Camilla on their return procession.
There were more than 1,000 route liners from the Army, RAF and Royal Navy.
Charles and Camilla entered Buckingham Palace through the centre arch at around 1.30pm.
At about 2.30pm they were joined by members of the royal family on the palace balcony to watch the flypast.
Prince Harry was not involved in the balcony moment and is understood to have been driven away to the airport after the ceremony.
He appears to have snubbed an invite to a lunch with the rest of the royals.
