In the summer of 1969, Newsweek published an article under the headline The Girls - Letting Go, charting the burgeoning careers of a group of young musicians it termed "a new school of talented female troubadours". They sang about politics, love affairs, the urban landscape, drugs, disappointment, and the life and loneliness of the itinerant performer - subjects that, hitherto, had largely been the preserve of male musicians. "What is common to them - to Joni Mitchell and Lotti Golden, to Laura Nyro, Melanie, and to Elyse Weinberg," the writer, Hubert Saal, observed, "are the personalised songs they write, like voyages of self-discovery ... what they celebrate is the natural, preferring the simple joy to the complex, the artless to the artful and, rather than the holding back, the letting go."

There have been many "new female troubadours" in the years since - from Patti Smith to Lucinda Williams, Emmylou Harris and Carole King - all of them writing and singing across a period in which women's liberation made great strides. Today, almost 50 years since Saal's article, women's lives are markedly different from the way they were in 1969, but has the world of women in song evolved as markedly?

We are at a peculiar point in the music industry: female artists such as Taylor Swift, Beyoncé and Katy Perry have been among the industry's top earners in recent years, yet women's presence elsewhere in the industry is sparse, and female performers are thin on the ground at the summer music festivals. While this has generated much media discussion, how have female songwriters responded?

This early stretch of the year brings releases by several songwriters who might fall into that "troubadour" category. Artists such as Laura Marling, Courtney Marie Andrews, Julie Byrne and Nadia Reid are writing songs that capture the pulls of both domesticity and the road, and what it means to be living a life that does not entirely tally with convention.

Marling's sixth album, Semper Femina, follows last year's Reversal of the Muse podcast series, in which she spoke to musicians such as Dolly Parton, Emmylou Harris and Marika Hackman, as well as women elsewhere in the industry, such as guitar shop owner Pamela Cole and recording engineer Olga FitzRoy, to explore femininity in creativity - from the challenges of writing, recording and touring, to the masculine design of guitars and the fact that women hear differently from men.

"I would say that feminine creativity is inherently different from the masculine," says Marling. Even at its beginnings, she suspects that women's musical impulses have different motivations from those of their male counterparts. "I had a lot of chats with Blake [Mills, Semper Femina's producer] when we were making the record, about how we started playing guitar," she says. "And he was like: 'I started playing because I wanted to impress girls.' And that was obviously so different from why I started playing guitar - that was never in my brain, to impress boys. So even that crucial difference makes for a different musician. For me, playing guitar has always been tied up with my identity rather than enticing people in, it's always been involved in myself."

This album emerged after a time in which Marling felt that she had become increasingly "masculine" - determinedly touring alone, lugging her own gear, stepping away from ideas of feminine dress. While this stretch was not long-lived, she believes it gave her "an ability to look at women in a different way and consider how I'd been looked at". She is resistant to being pigeonholed. "I think, when I was a teenager, in my head you were either this delicate tragedy or you were a muse," she says. "And they're both such horrifyingly subjugated roles."

She was struck, too, by an old edition of Desert Island Discs in which Marianne Faithfull was the castaway. "The presenter said: 'So, tell me, you must have felt very hard done by that all the Rolling Stones deserted you?' And she said: 'Can you stop trying to make a tragedy of me? I'm not a tragedy! I've lived my life. Obviously, I was a drug addict, but I was always going to be a drug addict. I had an amazing time!' And it's true, by any other masculine name, all those experiences would be clocked up as experiences and nothing more."

But ideas of what women in music should be are hard to shake. There is an impulse to make an easy tragedy of female musicians who have spent their lives on the road. There is something, too, that expects women to be static, indoor, domesticated and "confessional" songwriters. As the late John Berger put it: "Men act, women appear."

Crucial to this is the idea of women and movement - women stepping outside the safe confines of the home and domesticity. For Julie Byrne, the compulsion to keep moving has run in tandem with her career as a songwriter. "I was always fascinated by that lifestyle," she recalls. "When I was living in Buffalo, New York, where I'm from, there was a huge contingency of freight-train hoppers. There was a pretty legendary house in Buffalo called the Birdhouse that was well known in that network. So there was this huge influx of travellers in the summertime, and there'd be really glorious parties with music until the early hours ... I think this was probably where this sense of wonderment came from."

In her teens, a year after she began playing music, Byrne toured with some friends, travelling through Pennsylvania, Ohio, Tennessee and South Carolina. She remembers the joy of that time - the new landscapes, playing live, trying to navigate their way to the next city in the days before Google Maps and smartphones. "I think it just strengthened all the curiosity I had," she says. "I wanted to continue to learn through my experiences that way."

This is not to suggest it was without problems. "We were in my friend's old Volvo that had a leak in the gas tank," she says. "We ended up running out of gas and were stranded on the highway somewhere outside Memphis. That was my first experience of being outside New York state and everything was enchanted. Breaking down, all of it. There was poetry in everything for me then, and I think a lot about that time, how moving just the most mundane aspects were for me when I was younger."

Her experience of the touring life has changed with the years - while she retains some of that early wonderment, she also sees its limitations. Her most recent album, Not Even Happiness, was written largely in the time that Byrne was touring its predecessor, Rooms With Walls and Windows, when she gave up the place she had in Seattle, along with her furniture and most of her belongings, "because I couldn't afford to maintain a room somewhere while I was on the road constantly".

That weightlessness brought a new quality to her music. "A lot of these songs come from the power and the beauty of travel and of relying on the generosity of other people," she says. "But also the pain of not having any privacy and not having anywhere to go to weep for the condition of the world or the condition of my own heart, so that was a time of extreme vulnerability. But I think that brought on some meaningful realisations in my life - that you carry your burdens wherever you go, and they don't just fall away just because you're across the country or in a different setting. They stay with you until they're resolved in some way."

Courtney Marie Andrews left her home in Phoenix, Arizona, when she was 16 and began busking along the west coast of America. "I just fell in love with the lifestyle," she says. "At that time I was so young and so ready to get out of Phoenix - I just felt trapped there, and I realised there was so much more to the world. I loved making music with my friends every day, and being in different cities. I thrive on change, and I really felt drawn to the constant movement."

She soon found work, first as a backing singer for other artists, then playing lead guitar for Damien Jurado, and her life on the road ran on. It was only more recently, after the end of a serious relationship, that she began to consider the drawbacks of a rootless lifestyle. It is a subject she addresses on her latest album, Honest Life, setting all the nights of travelling, playing, eating alone in diners and sleeping in vans against the pleasures of a home and community.

"I wrote those songs because I realised I'd spent pretty much my entire later adolescence and early 20s on the road," she says. "I'd come home and people had cultivated these really in-depth relationships, and I started to pine for that. I'd be home just for a month and that would be it. The pluses are playing your songs every night with your friends - you can't really complain. But the thing you miss is the human connection. That can become really hard. You say: 'Hi, my name's Courtney!' 500 times on a tour."

The trials of life on the road is not an unfamiliar subject for songwriters, but for female musicians there are additional weights: centuries of women being expected to stay at home, as well as the constrictions of time and biology; the music industry is not set up to accommodate parenthood, let alone the physical demands of motherhood. There is also the suspicion that greets women who don't quite conform.

For Byrne, life in freefall is something that can grant women's songwriting extra force and insight. "I think that women living lifestyles with no fixed home and really having to be at the mercy of that experience will probably transcend that [more traditional] mould," she says. "I think women have a certain vision that is so deeply connected to their interior lives, and I think women are inherently willing to be very vulnerable, and have an honesty that they're willing to share with other people. And that's the most powerful thing there is."

Andrews is similarly hopeful that these songs of the road will still have the capacity to affect their listeners. "It's so funny, I always thought, 'Well, this is just how it is,'" she says. "But it's very true - [traditionally] men touch on this life in their songs and women talk about domestic issues or their husbands. But I hope that women, or just people in general, can empathise with those stories coming from a woman. Because anybody can live that kind of lifestyle."

Nearly half a century after that first wave of new female troubadours, it seems women songwriters are still muddling out a way to be. But however gradual, what we are witness to is still an evolution, a slow bucking of convention, women singing songs that tell of a new life and its possibilities; 50 years on they are still letting go.

Not Even Happiness by Julie Byrne and Honest Life by Courtney Marie Andrews are both out now. Semper Femina by Laura Marling is due for release on More Alarming Records on 10 March.