“I never doubted that David Trimble truly believed in the Union,” says Dame Arlene Foster.

Loyal to the Union, David Trimble was known among his fellow union members as an intellectual giant, a man of detail, but also as a man who could be blunt with anyone who crossed his path.

Former First Minister Arlene (now a Dame) Foster began her political career with the Ulster Unionists before defecting to the DUP over aspects of the Good Friday Agreement.

She said history “will favor” the man who brought Ulster Unionism to the negotiating table.

“I was at an event at Queen’s when he was honored at the end of June. I am shocked to learn of his passing so soon after,” she said.

“David was an intellectual trade unionist, he wasn’t someone who rose through the ranks in the usual way, he came from an intellectual standpoint. That was his strength and, in a way, his weakness.

“It is known that I left the Ulster Unionist Party and that we had disagreements, especially over the Belfast Agreement, but I never doubted that he, like me, deeply believed in the Union.

“I was glad that I had the opportunity to speak with him in June.

“I think David understood why I couldn’t support the Accord, especially regarding the victims and the release of prisoners, but I never questioned the foundations of the Accord in terms of the constitution.

“I think history will be kind to David because he got the constitutional question right in the Belfast Agreement because the status of Northern Ireland will not change until the people of Northern Ireland say otherwise. He got the big picture right.”

Politically active to the end, Lord Trimble most recently campaigned against the Northern Ireland Protocol and called in the High Court a challenge to the “Irish Sea Boundary” which he believed violated Northern Ireland’s constitutional status.

“He was the plaintiff along with me, Kate Howey, Jim Allister and Ben Habib against the government in an ongoing case,” Dame Arlene said.

“Thus, his legacy will always be the protection of the union, until his death.”

Jonathan Kane, now Lord Kane, was a special adviser to six Conservative Secretaries of State, and few know more about the behind-the-scenes negotiations in the early days of the peace agreement.

The first ceasefire negotiations and paramilitary agreements took place under John Major’s government, and when the Tories lost the May 1997 general election to an overwhelming Labor majority, Tony Blair took over and secured an agreement along the line.

Lord Kane first met David Trimble in 1989 at a Friends of the Union event in east Belfast.

He said it was “unfortunate” how the Blair administration treated the UUP leader.

“I am saddened by the news of his death,” said Lord Kane.

“His legacy must be enormous, he was instrumental in securing this deal in 1998, a deal that marked a milestone in Northern Ireland’s history.

“Never underestimate this.

“It was David Trimble and John Hume who made the 1998 agreement from which everything else flowed.

“I am a frequent visitor to the States, and it saddens me that Trimble and Hume, and especially Trimble, were expunged from the history of the Accord when he played such an important role. His fellow union members must ensure that his legacy is now properly remembered.”

Lord Trimble had a fearsome reputation – being on the wrong side of his anger was uncomfortable.

Lord Kane said: “He had a reputation as the ‘angry man’ of the trade union movement, and no one will deny that he can be blunt, but in my dealings with him he never came across as embittered. Perhaps he was disappointed.

“To put it mildly, it was unfortunate that in 2003 the Blair government abandoned him, but I would not like to dwell on it.

“He had a sharp mind, he was a staunch trade unionist, a committed tradesman, but when the time came he realized that a deal had to be struck for the benefit of all the people of Northern Ireland.

“He was able to bring unionism into line with nationalism, and for that he deserves great credit.

“And to all this he was a good friend, a good colleague in the House of Lords and a man of great wisdom.

“He’s there with Carson and Craig, and with the giants of Ulster Unionism.”