Jane Birkin began keeping a diary aged 11, with the entries addressed to her beloved stuffed toy Munkey. She was born in London; her mother was an actor and her father a spy during the second world war. Birkin’s concerns, initially, were typically teenage – boarding school, boys – but quickly become more juicy: aged 18, she married the James Bond composer John Barry; a year later, she appeared in Michelangelo Antonioni’s Blowup. In her 20s, she became involved (creatively and romantically) with the French musician Serge Gainsbourg and set out on a lifelong path of singing, acting, writing and being one of the most renowned muses of the 20th century and beyond. Now 73, she lives in Paris with her bulldog – regularly seeing her daughters Charlotte Gainsbourg and Lou Doillon, who are both actors and musicians; her oldest daughter Kate Barry, a photographer, died in 2013. Munkey Diaries: 1957-1982 is published this month.
Can you introduce Munkey?
Ahhhh, I think my father’s brother won him in a raffle. It might have been at a pub. He was very jaunty with his beard and jockey cap, a rather gaudy character. And I adored him, so my Munkey became something that was a part of all our lives. My father had his pyjamas. Serge had a pair of his jeans. My daughters had capes that were made by my grandmother, therefore that counted as magical clothing because they were made before I was 14. I left my Munkey with my father or Serge when they had an operation. We never took an aeroplane without Munkey. We never took a train without Munkey.
And you never lost him?
Amazing! For me who lost nearly everything. And he got better with the years, because his face on the cover of [Serge Gainsbourg album Histore de] Melody Nelson is much more attractive than when I first got him. So by the time Serge died [in 1991], the children – Kate and Charlotte – were so distressed, I didn’t know what to put in the coffin that would make the children feel that he might be a bit safer. So I ran back home and I got my Munkey and I put him in with Serge. Which is a crazy thing to do, but better than to have lost him in a stupid hotel or to have any other idiot thing that could have happened to him.
You have kept a diary for most of your life – what do you like about them?
My parents gave me a diary, like lots of little girls. And I gave my girls diaries as well. I mean, I gave them secret diaries with padlocks, but in fact, mine were just exercise books. And it’s a rather good thing to keep, because you can have a good laugh later on about the tiny things that made you miserable.
You were more inclined to record the bad things that happened?
Well, I think that diaries are very unfair. Because one has a tendency of writing when you’re sad; when you’re happy, you’ve got lots of better things to do. When I read them, I find myself extremely tiresome. It must have been such a drag for John Barry to come back home and there you’ve got this waif-like 17-year-old who is there running his bath, giving him his newspaper. When I look back at that I think: oh my god... I only saw my side of the story.
Was it different with Serge Gainsbourg?
I really came into my own with Serge because he did nothing all day long but think of jolly things to do with me. So I was extremely happy. He was as jealous as I was. And although now people consider him as really quite a genius in France, which indeed he was, he was never a boring genius. He never said: “Well, now I’m going to go up to work.” I never saw him work. No, when I did rather bad films, he had a tendency of writing his best stuff because he was pissed off that I was not there. He used to come on to all the film sets, then sit miserably in the hotel bedroom where he wrote The Man With the Cabbage Head or Melody Nelson. In that way it was a rather ideal 13 years.
There’s a story in the book about how you threw yourself in the Seine after an argument with Gainsbourg. You describe him as a fan of “grand gestures” – would you say the same thing about yourself?
As we were both plastered, the grand gestures came rather easily. Also, not being too stupid, I realised I’d done something so outrageous that I had to do something pretty enormous to win him back again.
What did your daughters think of your diaries?
Neither of them read them. Lou said in a rather frank interview she gave: “Who’d want to read their mother’s diary?” That said it all. Put me in my place.
What book would you recommend for a young person?
Well, I’d say they should discover Graham Greene. My favourite book is The Heart of the Matter, or Brighton Rock; they should read Brighton Rock immediately.
Didn’t you meet Greene?
Yes, I did his play Carving a Statue when I was 17 and he was involved in the casting. He had an extraordinary face, his eyes were so blue, it was like looking straight through to a blue sky through a skull.
What was the last really good book that you read?
I have just read Les Misérables, [Victor] Hugo, which I’d never read before. I’d started [it] I don’t know how many times, so I thought I’d plunge in. All the characters are wonderful, one sort of knew them, but they’re even better when you read them. And you find all the bits of Paris that you didn’t know, or rather you did know but these people lived there. You have to put up with him being a bit historical, so I used to jump little bits. But then in War and Peace I used to jump a little bit of war as well.
• Munkey Diaries: 1957-1982 by Jane Birken is published by Weidenfeld & Nicolson (£20). To order a copy go to guardianbookshop.com. Free UK p&p over £15