Historic Foreign Office documents have cast a light on the homophobic policies that banned gay people from openly serving.

A paper released today by the Foreign and Commonwealth Office sheds light on historical FCO policy towards gay employees, who were actively persecuted for much of the 20th century.

Until 1991 gay men and lesbians were officially barred from working for the British Diplomatic Service, and many went to great lengths to conceal their sexuality.

While the ban was in place. the official Foreign Office line was that gay officials might be subjected to blackmail from a hostile intelligence service.

However, FCO Historians questioned this historic assertion, suggesting that “the primary reasons for the maintenance of the sexuality bar had less to do with the threat of blackmail than they did with deep-rooted cultural attitudes at the FCO”,

The booklet recalls: “Numerous individual cases throughout the 1960s, ‘70s and ‘80s demonstrate that gay men were interrogated, made to recount in detail the exact nature of their private sexual lives, and then quietly retired or moved to another government department.

“Indeed, so widespread was the practice of ‘burying’ such cases that at a meeting in 1972 one FCO official reported that ‘the DHSS bewailed the

fact that … their ranks were swelling with Communists and homosexuals’.”

The documents also shed light on internal discussions within the FCO.

In the 1980s, one official said: “I am in favour of erecting a notice, ‘No homosexuals should apply’ on the perimeter of the Service”.

Meanwhile, there was much discussion of whether lesbianism also posed a risk.

A 1975 document suggests lesbians were a lower security risk, explaining: “Lesbians are believed to be less promiscuous than male homosexuals and to be more inclined to establish a stable domestic set-up with a single partner. They may perhaps therefore be emotionally more stable than male homosexuals.”

In 1981, a diplomat affirmed this, writing: “There is very little lesbian prostitution; lesbian relationships tend to be relatively stable; there is not the same widespread interest among lesbians in very young sexual partners as there is among male homosexuals, and the female ‘gay’ scene is much less commercialised than the male.”

The ban was eventually lifted in 1991, when Sir John Major announced that ‘changing social attitudes’ meant that homosexuality should no longer be a barrier to employment in the Diplomatic Service.

James Southern of FCO Historians said: “If we are to make today’s FCO a tolerant and open institution, then it is vital we understand its past.

“I hope this publication and event go some way to help all of us realise that we have a shared history and a shared responsibility to shape the present.”

Simon McDonald, Head of the British Diplomatic Service, said: “I am proud to lead an organisation with a diverse workforce which stands up for people persecuted around the world because of their sexuality.

“But it’s important we don’t hide the past and are honest about our mistakes. We changed our attitude to homosexuality, and now set an example for others.”

Lucy Monaghan of the Foreign Office’s network for LGBT Staff, FLAGG, said: “This report shines a light on the history of the sexuality bar in the FCO and the significant struggles many LGBT officers experienced.

“We hope it will enable the FCO to learn from its history and continue to stand up for LGBT rights within the FCO and across the world.”