Much had been said and written ahead of the meeting between the deputy first minister and the monarch at Belfast’s Lyric Theatre.
But the title of the venue’s current play summed up the mood of the day — Oscar Wilde’s The Importance of Being Earnest.
The momentous meeting took place in a building representing the new face of Belfast — an £18m (€22.5m) theatre just over a year old. It replaced an earlier 1960s performance space but the ethos behind it remains the same — working with actors, directors, and behind-the-scenes staff from all communities.
The Queen and Mr McGuinness’s first greeting took place out of sight but not out of mind in a corner of the theatre away from the chatter of invited actors, artists, schoolchildren, and local dignitaries.
They were there to celebrate the arts on both sides of the border — unity through a love of literature, paintings, or the theatre, whether one was Catholic or Protestant.
Inside a sparsely furnished room where budding actors are put through their paces in drama workshops, Mr McGuinness and the Queen shook hands.
The McGrath Suite is clad in contrasting Belfast brick and West African Iroko hardwood — a marriage of the traditional and the exotic — and was furnished with modern leather chairs.
And if they had opened the curtains covering the floor to ceiling windows, they would have seen landscaped lawns and Belfast’s Lagan River.
With the meeting lasting around five minutes, it is not known if there was time to talk over tea for those in the room, who included President Michael D Higgins and his wife Sabina, the Queen’s husband Philip, and the North’s first minister Peter Robinson.
When the group emerged, Mr McGuinness mirrored Philip at one point, walking with his hands clasped behind his back, as they followed the Queen into the theatre’s café bar to see an exhibition.
The two men stopped to speak to acclaimed poet Michael Longley, who stood beside his striking portrait which was painted by Colin Davidson, who chatted to the monarch.
Mr McGuinness and the Queen’s consort looked at ease in each other’s company and both commented about the painting.
Mr McGuinness waited patiently out of shot when Mr Robinson presented the Queen with a gift from the Northern Ireland Executive, a one-off handcrafted Belleek fine bone china bowl.
A line-up of dignitaries is usually a prerequisite for the departure of the Queen, when she thanks her hosts and they in turn say goodbye.
Mr Robinson was first in line and as the Queen appeared he held out his hand.
Next was Mr McGuinness, who spoke an Irish blessing while still holding onto the Queen’s hand, translating it for the head of state: “Goodbye and God speed.”
When Mr McGuinness left a while later, journalists shouted questions at him asking how things had gone. For those who might think the Queen’s well-known wit and easygoing nature had completely won over the former IRA commander, he replied: “I’m still a Republican.”
According to Sinn Féin, Mr McGuinness greeted both the Queen and President in Irish, saying: “Céad míle fáilte romhat.”
The party said he commented briefly on the Queen’s visit to the Republic last year, and the sympathy she expressed for all victims of the Troubles.
“He emphasised the need to acknowledge the pain of all the victims and their families,” a spokesman for Sinn Féin said.
“He spoke of the significance of [the] meeting and the need for it to be built upon. He said the fact that it was happening at all was a powerful signal that peace-building requires leadership.”