The protestors at The Grill pub in Union Street, Aberdeen, mobbed this once-conservative establishment after the landlord tried to stop them getting through the door.
Police were called to break up the “invasion” - as newspapers of the day described it - with the women demanding to finish their drinks before being escorted from the premises.
It was another two years until the Sex Discrimination Act did away with male-only public houses but it took The Grill - one of Aberdeen’s most famous bars - until 1998 to instal a female toilet.
Now, 45 years after the original protest, a film is being made in Aberdeen to celebrate the stand taken by the women with “No Ladies Please” to be released later this year.
Aberdeen-based historian Dr Fiona-Jane Brown, who wrote the script, said: “This is so timely, given all we are still hearing about inequality of the sexes. I think it is really important to hear this story.”
Director Yvonne Heald added: “The film is even more relevant today, given the issues of abuse in the workplace and women’s position in society in 2018.”
It was George Robertson, then Scottish organiser of the General, Municipal and Boilermakers’ Union and later secretary general of NATO and now member of the House of Lords, who led the protest at The Grill.
He was attending the STUC conference at the Music Hall when he visited The Grill during his lunch break.
During an afternoon session back at the conference, he told delegates: “This bar has a simple little sign on the door which says ‘No Ladies Please’ and that is the sort of thing that this motion is trying to stop.”
A newspaper report added: “Then amid hearty cheers, he threw out the challenge ‘if any women here are willing to go there at five o’clock and ask for service, I am willing to support them.”
The report continued: “And at opening times, which coincided with the end of the day’s business in the Music Hall - the women stormed across to Union Street accompanied by their male escorts.”
The women “took up their battle stations” six deep at the pub door before breaking out into a spontaneous chorus of We Shall Not Be Moved.
Mr Eddie Watson, the pub owner, was greeted with “boos and cat calls” when he told the gathered group “sorry no ladies.”
He attempted to close the doors but the women pushed forward and “within seconds the pub was full to capacity,” the report said.
Susan Hamilton, national branch secretary of the National Union of Public Employees and a member of Hamilton Trades Council told reporters: “We were talking about discrimination today and we decided to take immediate action.
“That is what I am doing here - and I also need a drink.”
The report added: “During the rush the ‘no ladies’ sign was snatched off the bar door and was passed triumphantly from one group of victorious delegates to the next.”
The Grill was not the only pub in Aberdeen to preserve a male-only environment until the 1970s.
The Bridge, the Pittodrie and the Central were all keeping out women until 1975 when the Sex Discrimination Act was passed.
On the eve of the new law, newspapers in Aberdeen reported the confusion surrounding the new era of equality.
The Grill and The Bridge bar had no toilet for women, with landlords concerned they would be breaking the terms of their licence if they served a woman without the proper facilities in place for them.
But a deeper wish to keep women out of the pubs was also expressed.
The manager of the Bridge bar told reporters on the eve of the new law: “If we let women in here, half the men would walk out.”
Dr Brown said, following the new equality legislation, women at The Grill used the men’s toilet and got a friend to stand at the door.
She added: “For a long time in Aberdeen, there were a lot of pubs where you didn’t go in if you were a woman.
“But after 1975, I know that a lot of women made a point of going to The Grill.”
No Ladies Please, which is being made with Crow House Projects, is in post-production with a Crowdfunder raising the final funds required.
The majority of funding for the project came from Aberdeen City Council.