Axel Scheffler: ‘To work for children, you must have optimism’

Illustrator and author Axel Scheffler: ‘As a child I drew lots of animals – cartoony drawings in the margins of my exercise books.’ Photograph: Alamy

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.