I first met Jim Callaghan when, in opposition after his period as home secretary dealing with the early stages of the Northern Ireland crisis, he called to see me at home to discuss his ideas on the future evolution of the North.
But I did not get to know him well until after his appointment as foreign secretary by Harold Wilson, following Labour's return to power in early 1974.
While in opposition his party had committed itself to renegotiating Britain's terms of entry to the European Community. As foreign secretary in 1974-1975 he was somewhat uncomfortably placed vis-a-vis his EEC colleagues, who, though anxious to help a colleague whom they rapidly came to respect and like, were not prepared to turn the whole structure of the Community upside down just to get his government off a hook on which it had impaled itself before coming to power.
However, with great political skill, he succeeded within a year in persuading British opinion that the fairly minor concessions he had secured, such as increased access to the EC market for New Zealand butter, represented a sufficiently successful outcome to this negotiation to warrant a positive vote in a referendum on EC membership.
As it happened, his appointment as British foreign secretary had come just before the holding of a two-day informal meeting of the nine EEC foreign ministers, accompanied by their wives, at Gymnich Castle, near Bonn; at that time Germany held the EEC presidency.
At an early stage of that meeting Jim Callaghan asked his new colleagues what the recent Copenhagen summit of heads of government (which had been attended by Ted Heath shortly before his election defeat) had meant when they had announced an intention to create a "European Union".
He was, I think, considerably reassured when most of his colleagues explained that they hadn't a clue as to what this had been meant to mean! The phrase had been coined simply to obscure the failure of that unhappy post-oil-crisis meeting of EC heads of government.
That evening our host, German foreign minister Walter Scheel, who had a great reputation as a singer, brought us down to the castle cellars for a sing-song, in which Jim Callaghan and my wife, Joan - but few others - joined enthusiastically. When Jim Callaghan suggested singing Tipperary, Joan's semi-humorous protest at a German foreign minister being asked to sing a British song of the Great War was instantly swept aside by Scheel, who launched forthwith into its verses.
The Paris summit held at the end of that year resolved, among other things, to end the abuse of the veto in relation to decisions that did not involve vital national interests and which, under the terms of the Treaty of Rome, were supposed to be taken by qualified majority vote.
When the first Irish EEC presidency started a few weeks later, I sought to give some effect to what may have been something of a pious resolution, by introducing a new procedure. This involved identifying at the start of each council meeting those items on the agenda that required unanimity and those that should be decided by qualified majority under the terms of the Treaty of Rome.
Then I would ask the ministers to say in advance whether they would accept such a vote on decisions that fell into the second category.
At every meeting Jim Callaghan - but only he - protested against this procedure, but as it happened it was only at the last meeting of that Irish presidency that an issue to be decided by qualified majority actually appeared on the agenda.
Jim Callaghan wanted meat from Botswana and Swaziland to be admitted to the Community free of import levies. Everyone agreed in principle that this should be done, but France and Germany could not agree on whether the levies should be remitted, or should first be paid and then refunded.
It was worth seeing Callaghan's face when I called a vote by qualified majority vote on that issue - a vote that, of course, he had to accept in order to secure free access for this meat.
When a conference between developed and developing countries was called in 1975 Jim Callaghan sought separate British representation at it, although he must have been advised by the Foreign Office that, as the issues involved were Community competences, separate national representation in parallel with a Community delegation was impossible.
When the Times of London interviewed me just before a foreign ministers' informal meeting in Lucca, and I explained this situation, the paper made this the main story next day. So I was met at Lucca by a grim-faced Jim Callaghan, who was even uncharacteristically cool to Joan.
Even when other ministers and the president of the Commission backed me up by explaining why separate British representation was impossible, he persisted in bringing the issue to the next European Council in Rome in December 1975.
There Wilson and he sought to disguise their inevitable failure on this matter by holding their post-European Council press conference in the British embassy, well away from the conference venue where other prime ministers were briefing their journalists.
The Telegraph and the Times were taken in by this manoeuvre, but the Financial Times, whose four correspondents attended all 10 briefings, and the always well-informed Guardian correspondent, accurately reported the British defeat.
Jim Callaghan had not lost his interest in Northern Ireland, and in August of that same year, while staying with their daughter, Margaret, and her husband, Peter Jay, at their house in Glandore they asked Joan and myself - we had rented a house in nearby Schull - and Jack and Máirín Lynch to dinner.
I was glad of the opportunity - with strong support from Jack Lynch, then leader of the opposition - to unburden myself of our government's frustration with Northern Ireland secretary Merlyn Rees's extraordinary behaviour in authorising discussions with Sinn Féin, aka the IRA, during the course of that year, while absolutely refusing to meet me as Irish foreign minister, lest I quiz him about these Sinn Féin contacts.
I warmly welcomed an after-dinner offer by Jim Callaghan to arrange a three-way meeting between myself, himself and Merlyn Rees. It never took place, however, apparently because Rees was furious at Callaghan's intervention and rejected the idea of such a meeting.
Before the holiday ended Joan and I welcomed Jim and Audrey Callaghan in turn to our rented house (Jack Lynch had to return to Dublin for a last interview with a dying Eamon de Valera). Jim Callaghan liked the house so much that he wondered if there would be any chance of buying it next year when, he told me, he intended to retire; for, he said, he wouldn't become prime minister after Harold Wilson, because he was older than Wilson.
In the event Wilson retired some six months later, and Jim and Audrey Callaghan never acquired a house in west Cork. But they did return there to stay with their daughter and, in 1990 I think, once again dined with us, an evening that ended with a "Jim and Joan" sing-song in memory of the Gymnich cellar.
Then, as always, one could not but be conscious of how close Jim and Audrey were to each other.