There was an obvious sense of anger about the crowd, fuelled largely, it appeared, by the realisation that their gesture would be in vain.
But the symbolism was blunt and striking. With Stormont Castle silhouetted behind them the crowd swarmed around a statue of Edward Carson, the grand figure of Unionism and one of the founders of the Unionist state in Northern Ireland. Beneath the statue the crowd continued to protest, arguing that they were being sold out by the on-going talks. Many carried Union Flags and the red hand Ulster flag.
The Rev Ian Paisley appeared and addressed the crowd asking them to go home, their protest having been made, but he was ignored.
The leader of the Democratic Unionist Party was then allowed through police lines and hijacked the press briefing room. His arrival with fellow DUP MPs, the Rev William McRea and Peter Robinson graphically underlined a looming potential split within Unionist ranks over the deal the official Ulster Unionists and other parties were expected to sign today.
He was greeted with shouts of "how many of you people fought in the British army?" and "what about the loyalist prisoners?", from political opponents who tried to sabotage his press conference.
Earlier at the gates of Stormont Mr Paisley had decried the talks process as a sell out. "They do not want democracy," he said, "and we are seeing tonight the jackboot of what will happen if this deal goes through.
"Inside these gates there are scores of IRA men with illegal weapons."
As the midnight deadline passed the crowd managed to breach the line of officers, swarming past Carson's statue and heading towards the Castle Buildings, the part of the estate where the talks have been taking place.
They were stopped again by police reinforcements about 300 yards from where the party leaders were still talking. At this stage Mr Paisley appeared again, cheered by the crowds who continued to chant and sing the national anthem.