Trade union leader Jack Jones, 1913-2009

In 1977, the majority of people in Britain thought Jack Jones was more powerful than the prime minister. This wasn't strictly true, said Terry Pattinson in the Independent, but the fact people believed it – he was dubbed 'Emperor Jones' by his critics – reflected the dominance then exercised by the unions, and in particular by the Transport and General Workers Union (TGWU), of which Jones was General Secretary from 1969 to 1978.

In this capacity, he made the government dance to his tune, improving conditions for workers across the country with salary and pension hikes, regardless of whether these benefited the broader economy. He was bitterly attacked, but few doubted his integrity.

Scorning the trappings of grandeur, he refused a peerage on retirement, and remained in the council house he and his wife had occupied for many years. As Jones himself put it: "All I have ever been is a soldier in the great army of labour. I have been proud to serve the union of working people. There is no greater calling than that."

James Larkin Jones, who has died aged 96, was born in the slums of Liverpool, the son of a docker. He started work on Garston docks aged 14, said the Times, soon working his way up the TGWU hierarchy, and becoming a Labour councillor by the age of 23. In 1937, he crossed the Pyrénées to fight against Franco.

Wounded at the Battle of the Ebro ("I had been given a black leather jacket before going to Spain," he recalled, "and foolishly insisted on wearing the bloody thing, which made me rather visible"), he returned to Liverpool, where he delivered a friend's dying words to the man's widow, Evelyn Taylor. The encounter led to a marriage lasting 60 years.

In 1938, the couple moved to Coventry where Jones was made district secretary of the TGWU. There, his "appetite for work" and "obdurate" negotiation skills served him well. Exempted from military service in WWII, he set about persuading the bosses that ceding influence to shop stewards would improve efficiency and help the war effort.

Some argue it was Jones’s intransigence that led to Thatcher’s victory in 1979

Jones helped to keep Coventry's munitions industry working throughout the Blitz of 1940, said the Daily Telegraph, without ever relaxing his aim of bettering working conditions. In 1946, he won a five-day week for workers at Standard Motors, later introduced nationwide, giving the working-class a full weekend for the first time (to the "deep concern of some moralists").

Thanks to his haggling, Coventry's car workers gained the country's highest shop floor wages, and, from 1951, two weeks' paid holiday. Jones's prestige within the unions grew, and in 1969, he was elected General Secretary of the TGWU, by 520,000 votes to 28,000.

In the following decade, Jones was able to bend both Labour and Conservative administrations to his agenda – amid "endless sessions of beer and sandwiches" at Downing Street. In 1969, when Harold Wilson tried to tame the growing power of the unions, Jones gave not an inch, organising a strike at Ford, and forcing the government to drop its industrial relations reforms – a major factor in Labour's 1970 election defeat.

Ted Heath tried to cultivate good relations with the unions but the "terrible twins" – Jones and the equally mighty Hugh Scanlon of the Amalgamated Union of Engineering Workers – would not contemplate any curb on wage bargaining. When Heath called a general election in 1974 on the question of "Who runs the country?", most people felt it was the unions, and Heath lost.

Jones played a crucial role in Heath's downfall, drumming up support for the crippling miners' strike. By 1975, the going rate for wage increases was about 30 per cent. Some have argued that it was Jones's intransigence that led to the strikes of 1978-9, ushering in 18 years of Tory rule, said Tam Dalyell in the Independent.

But after Heath's defeat, Jones did try to restrain wages. The Winter of Discontent was triggered by more extreme unionists, compared with whom Jones was constructive - and above all, humble. After delivering his farewell speech at the TUC conference in Brighton in 1978, he donned his beloved cloth cap, and walked off along the promenade to eat a bag of chips, while other union chiefs were whisked away in their executive cars. ·