Okay, this question about 'William' by E.H. Shepard keeps popping up! It's not based on a true story about a single, real boy named William Brown, but it's incredibly, deeply inspired by a real one.
Shepard's own son, David, was the primary model. The stories he brought home from school, his endless schemes with his friends, the scrapes he got into – all that chaotic, mischievous energy was funneled straight into William's adventures. You can practically hear Shepard chuckling to himself as he wrote down another of his son's exploits, just dialing the chaos up to eleven for comedic effect.
It’s also a product of its time, capturing the essence of a very specific English childhood between the wars. The freedom the kids had, the tussles with Victorians and the emerging modern world, the village fetes and strict governesses – it's all drawn from the life Shepard saw around him. So while William himself is fictional, he's a perfect, hilarious archetype built from the raw materials of real boyhood.
That's why he feels so authentic, I think. He’s not a made-up ideal; he’s the distilled spirit of every kid who ever tried to train a beetle or start a secret society, with the mud and the scraped knees left firmly in the picture.