Michael Mason: Journalist and activist who helped make the paper 'Capital Gay' a fun read, but with a serious side in the era of Aids

Mason's finest hour was being asked, in 1979, to lead the Pride parade in San Francisco on the 10th anniversary of the Stonewall Riots

Michael Mason was born into an era when male homosexuality was illegal – so it was remarkable for him, towards the end of his life, to see a Conservative prime minister championing same-sex marriage. Mason had used journalism as the foundation of a community that LGBT activists now take for granted. But he was also in a better position than most to know how far the Tory party had come.

In December 1987 the offices of Capital Gay, the weekly London paper he had co-founded, were firebombed. When Labour's Chris Smith, at that stage still Britain's only openly gay MP, mentioned the incident in Parliament, the Tory backbencher Elaine Kellett-Bowman called out "quite right too". She later defended her remark, saying she was "quite prepared to affirm that there should be an intolerance of evil".

For Mason and his colleagues, it was significant that nobody in Tory high command sought to rein her in; in fact less than a month later she was made a dame. The honour was doubtless already in the pipeline, so it wasn't a reward as such. But it could have been withheld if anyone in Margaret Thatcher's government thought it was a bad thing to advocate violence against gay property. They clearly didn't.

Michael Aidan Mason was born in Hammersmith in 1947. His father Kenneth was a Fleet Street journalist who went on to set up his own successful publishing house in Hampshire specialising in marine books.

Michael was sent as a weekly boarder to prep school in Surrey. Never one to wait around for the law to catch up, he was enjoying amorous adventures with schoolmates well before he moved on to Lancing College in Sussex. There he continued to enjoy himself, particularly in a space below the school stage. He was caught in the act when he was house captain, but was neither cowed nor shamed: he would reminisce about one particular beauty for decades to come.

He went on to St Edmund Hall, Oxford, where he read law, but that was not his chosen career. Instead he joined the computer firm IBM, honouring the terms of the university bursary the company had given him. But in the early Seventies his head was turned by the Gay Liberation Front, the celebratory new movement that had taken its lead from feminism and Black Power. He plunged into it, getting involved in groups and committees seven nights a week. It changed his entire world view.

After the GLF fragmented he got a job as business manager of the recently launched Gay News. In the mainstream press, the only stories about homosexuality were about teachers or scoutmasters getting into trouble. Spawned by the GLF, the new paper was more interested in community and activism. It was also an arena for debate, giving homosexuals the first chance they had ever had to talk to one another in public. Mason's public school and Oxbridge background was a source of mistrust at first, but within six months he was news editor. He was delighted when Tony Benn told him in an interview: "Good on you. Fight for your rights."

His finest hour was being asked, in 1979, to lead the Pride parade in San Francisco on the 10th anniversary of the Stonewall Riots. On their way to cover the event, he and his boyfriend Carl Hill had been arrested at US immigration because they were gay. On their release they found that they were minor celebrities downtown.

In 1981, he and his colleague Graham McKerrow broke away to launch Capital Gay, a free London tabloid for gay men, distributed mainly in pubs and clubs, which would embrace the new disco culture. As Mason put it, young people were going "straight from their nappies to the clubs" without any politicising in between, but there was still a lot of news that affected them.

Soon enough there was a story that would affect them massively, in the shape of a mystery illness from the United States. As frothy as it was, Capital Gay appointed a specialist columnist to write about Aids. The paper is credited by the Oxford English Dictionary as the first publication in the world to use the term HIV; indeed, its coverage was so far advanced even of journals that Aids clinicians considered it a must-read.

Capital Gay began to struggle after the launch of a brash rival, Boyz, in 1991. Reeling from a series of burglaries, the paper finally went broke in 1995, after Mason had passed on the editorship first to Gillian Rodgerson and then to me. He kicked himself later for turning down an offer of £250,000 from a big media house. It would have made him rich and saved the paper – but he thought at the time that it would be wrong to remove ownership from gay hands.

In later years he finally entered the law, as a legal secretary in a firm dealing with gay and lesbian immigration cases. He then joined the family publishing firm before buying a seafront flat in Brighton, where his retirement was cut cruelly short by cancer. Aside from Hill, with whom he spent a decade, he had a long-term relationship with David White, who now lives in Australia. He is survived by his father, Kenneth, his younger brother Piers and many loyal friends.

SIMON EDGE

Michael Aidan Mason, journalist: born Hammersmith, London 5 March 1947; died Brighton 1 February 2015.