When I started drawing the Gruffalo, I never thought I was drawing a character that would live in so many children’s minds. I thought it would be a picture book that sold a few thousand copies, like they usually do.

I gave the Gruffalo its overall shape – a monster with horns – and I decided he needed to be furry and he needed to have a tail. As I was sketching, I was thinking of medieval depictions of monsters. I found out later that Julia Donaldson had imagined him completely differently.

I don’t have a life philosophy. Life has been steady for me. No big ups and downs, just normal. Of course, my success has been extraordinary. That’s not normal. I don’t think many people create something as big and as popular as the Gruffalo. But I don’t know what conclusions to draw from that.

I was a happy child. I grew up in Germany, in a suburb of Hamburg. My family was that cliché, nuclear middle-class family of the 1960s: my mother was a housewife, my dad was a businessman. It was clear, very early on, that I wouldn’t follow in his footsteps. Drawing was what I wanted to do.

As a child I drew lots of animals – cartoony drawings in the margins of my exercise books. I discovered other people liked them and found them funny. I don’t think I was ever very ambitious. I didn’t want to be famous or rich. It kind of just… happened. I feel lucky to have achieved what I have.

I’m scared of the future. I’m scared for the generation that comes after me – for my daughter, all the other children. I worry about the planet. It all feels pretty dismal at the moment: the melting ice, the rainforests and coral reefs disappearing. I feel powerless.

I don’t like getting older. There’s lots of little pains and loss of memory. I’m not looking forward to the next period of my life. I don’t feel I’m very fit or healthy and I’m envious of older people who are, especially when they’re also healthy in their minds. My friend Judith Kerr was amazing. She was so young in her mind, right until the end, when she was in her mid-90s. If my old age is like hers, bring it on.

I don’t think I’ll ever stop drawing – until somebody tells me what I’m doing is getting really boring. But I do sometimes wonder whether I will carry on illustrating books. There are moments when I think ‘I’ve done enough now.’ Maybe I should start to paint.

I think people should follow their dreams. Don’t give up. Children often ask me what would I have done if I hadn’t been an illustrator? I don’t really have an answer to that. I don’t think I could have done anything else. Drawing is part of who I am. I don’t question it.

Creative skills like music, writing and drawing are part of being a human. When I do school visits I see how much children enjoy them. But these skills are neglected in education and in society. I think that’s sad. This country has a great creative industry and the government is just ignoring it. It gets less and less attention, less and less support. It’s depressing.

I cried not long ago, when I saw the first images of the Russian attack on the Ukrainian people. It was the fleeing women and children who brought tears to my eyes. It’s just completely unnecessary, this attack, this aggression. It’s so mindless. It should make all of us cry, all the time.

I’m more of a pessimist than an optimist. That’s not hard for anybody to work out. But I always say: as long as I do books for children, I must not have given up hope completely. To do work for children, you must feel some kind of optimism.

I’ll be remembered as the Gruffalo illustrator. I have no choice about that – that’s what I am now. It makes me feel slightly claustrophobic. Sometimes it feels like too much. I suppose that’s the flip side of success.

The Baddies by Julia Donaldson, illustrated by Axel Scheffler, is out now