After it was revealed by the Daily Mail she was living with a female journalist in 1977, Colquhoun refused to accept the prejudice she found aimed at her.
In a scathing article for Gay News she said her sexuality had “nothing whatever to do with my ability to do my job as an MP".
She went onto fight off efforts by constituency party members to stop her from running in the 1979 general election – although she eventually lost the seat to Conservative Tony Marlow.
Among the tributes which poured in after her passing was announced on Tuesday was one from Sally Keeble, who served as Labour MP for Northampton North from 1997 to 2010. “A short time in Parliament,” she wrote simply of her predecessor. “An indelible mark on public life.”
Labour's deputy leader Angela Rayner said the party had lost a "great sister" and described her as a “woman of huge integrity and courage”.
She said: “Throughout our party and our movement's history brave and principled women have been at the forefront of the fight for justice and equality for all, and we are reminded of that fact today by Maureen's passing.
"As the first openly gay MP she suffered great prejudice and indignity simply for being who she was. The fortitude with which she withstood the abuse she received is testament to her strength of character.
"Our progress as a party is thanks to the bravery and courage of Maureen and the women who followed in her footsteps…We stand on the shoulders of giants.”
Former minister Dame Angela Eagle, who herself came out while an MP in 1998, said that Colquhoun was “a feminist pioneer and paved the way for all of us who came after her”.
Colquhoun was one of fewer than 30 female members of Parliament when she was fist elected in 1974 – but she refused to be intimidated by such numbers.
She introduced a number of high-profile bills for greater female representation in public life, while also campaigning for greater support for working women and the decriminalisation of prostitution.
After the mother-of-three left her husband, the Sunday Times journalist Keith Colquhoun, in 1975, she asked the then Commons Speaker to refer to her as Ms rather than Miss in the Commons chamber – a request that was effectively refused.
After losing her seat, she worked for other MPs and served on Hackney Borough Council before moving to the Lake District, where she served as a member of the Lake District's National Park Authority for eight years.
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