The author on feminism, activism, The Color Purple and still being estranged from her only daughter

Pratibha Parmar's film Beauty in Truth, about your life and work, makes for fascinating viewing: you've done so many different things in so many different places with so many different people. Is that how it feels to you?

I'm still living at least five parallel lives, honestly! I wonder about it. I have no idea how that happens. But, yes, I live in Mexico, I live in Hawaii and I live in northern California and all my life has been like that. It's as if I got all of this energy from ancestors who were not permitted to leave the plantations for 400 years and I got all of their desire to be part of the world.

The film begins with your upbringing in Jim Crow Georgia, one of eight children, the daughter of sharecroppers. Your family had very little money, but you did have an extremely determined mother.

I think many people in my community had very different kinds of mothers: they had mothers who acquiesced in the system of male and white-supremacist domination and my mother never did. She just could not do it. It just wasn't in her.

You started writing as a child. Can you remember what you wanted to say?

I wanted to have a room of my own. It would be decades before I read Virginia Woolf and had her beautiful rendition of that thought, but I knew that was what I needed. The story that my mother tells is that, when I was crawling, she would look for me and I would have goneround the back of the house, and she would find me scribbling with a twig in the dirt.

You went to a school that your parents had helped to build and then went on a scholarship to college. But afterwards you went back to the south. Why?

In each of us, there is a little voice that knows exactly which way to go. And I learned very early to listen to it, even though it has caused so much grief and havoc, and I think that is the only answer. I was offered a scholarship that would have taken me to Paris, but I turned it down because I realised that my true responsibility was to go back and try to help people who were exactly like my family. So I listened to the little voice and got on the plane and went to Mississippi.

In your writing, you've tried to give a voice to your own family and to others like them.

I have, because I've wanted them to be seen in their radiance, in their humanity and their struggles and toils, which are so like everybody else's. There's nothing, really, I've found in my family that I couldn't find in almost any family on the planet, given the same circumstances.

Would you say that was your first motivation as a writer, to bring these hidden lives to light?

When I was 13, my sister was a cosmetologist – she made up the bodies in the funeral home. One day, she showed me the body of a woman who had been murdered. Her husband had shot her in the face. Now, many people would hear this tale, and they would categorise it; they would try to box it into some little corner, but actually that kind of brutality against women is endemic and it's now coming more and more out into the open.

That's something to see at the age of 13.

It had a big impact on me. And her daughter was in my class, and had the same name as my own grandmother, who had been shot to death. I think that, when you start out writing, it's often like following the thread of Ariadne: you never know which minotaur you're going to find. But you often find one – or two or three!

You were involved with the civil rights movement and with feminism, the latter especially when you moved to New York and worked with Gloria Steinem on Ms Magazine in the 1970s.

I love the women's movement and I never thought of it as belonging to any particular segment of the population. I loved working at Ms Magazine, especially because of Gloria, because she understood that I really needed a room of my own, even there.

What are your feelings about contemporary feminism?

The conundrum, in a way, is why, after all the struggle, and all the teaching – teaching was so important: we taught each other, and we taught other women and girls – women, at this point, are comfortable referring to themselves as guys, and basically erasing their femininity at every opportunity. I don't get it.

It's been 30 years since The Color Purple was published. Does it seem that long?

No, because time is always current, in some ways – there are people who are just discovering the novel today. And they write to me with the same fervour as someone else wrote 30 years ago. So the story is alive in that way and, even though I myself have written many books since then and rarely think about it in the same way that a fresh reader is thinking, it has its presence.

The attacks on Steven Spielberg's film version were extremely venomous. How did that affect you?

People abused me publicly, people who would start out by saying: "I have not read this book. I have not seen this film, but..." And the other side of that was that I was being censored, when they take your books out of schools, for years and years and years. It was hard and yet, again, I turned back to the ancestors, who actually are that little voice that says: "We know what we're doing," and I founded a publishing company, called Wild Trees Press, and started to publish other unpopular people.

In your fiction, you've always been determined to tell the truth. Is that what motivates your activism, too?

It's our only hope. The truth is the only guide. If you are led by a lie, of course you're going to fall off the planet.

You travel the world as a protester, but you also love solitude. How does that work?

It's quite an effort. I'll be 70 next year and 50-something years have been spent in writing and in activism, actually being on top of mountains and standing in crowds of people protesting. My road is a multi-directional road... What is helpful, though, is that I don't tend to respond to what is not calling.

You're very open about what it's cost you in terms of personal relationships, for example with partners and with your daughter [Walker and her daughter, Rebecca, are estranged].

I accept it. What can I do? I am this being who, for whatever reason, feels completely dedicated to the whole of humanity. I do. I deeply regret any harm, or any perceived harm, that I may have done to anyone by any behaviour of mine. I absolutely always tried to do the very best that I could with the spirit that I have.

What projects are you working on now?

I have two books. One is called The Cushion in the Road – it's about how, as a meditator, as someone who loves solitude, loves to be at home, I have my cushion and I sit there, but then the world calls and off I go.

And the other?

It's a book of poetry called The World Will Follow Joy. It starts with a poem about the Dalai Lama called "What Makes the Dalai Lama Lovable?" [laughs]

Do you still get great pleasure out of writing?

If it were not like that, why would I do it? It's about joy, if nothing else. That's what I think humanity has forgotten. This planet is for joy.

You sound like a pretty joyful person.

Well, why not?

Alice Walker: Beauty in Truth will have its world premiere on Sunday 10 March at Southbank Centre's WOW – Women of the World festival; southbankcentre.co.uk/wow