Celebrating its 50th birthday this spring, Dr Seuss's The Cat in the Hat remains one of the most loved children's classics and one of the the most analysed texts by academics, even being read as a metaphor for the state of American society prior to the Vietnam war!

"It's one of the most important books in terms of children's literature, " says Mags Walsh, director of Children's Books Ireland. "When it was first published, it had such a completely different style.

Teachers didn't like it, but children loved it. It opened up humour to children, and allowed nonsense to become sense. It sent out the message that it's fine to work nonsense into a book if it makes reading fun, and the fact that it's still one of the most popular read-aloud books for families, is its greatest legacy."

The book represents a watershed in American children's literature, being one of the first texts to bridge that gap between education and entertainment. The story of a cat who arrives unexpectedly and gets up to hi-jinks in the home of two children whose mother is out, The Cat in the Hat made it okay for children to overthrow the authority of their parents once in a while, a rare enough concept in the US in the 1950s.

The arrogant cat wreaks havoc in the lovely tidy suburban house, much to the horror of the household goldfish, who is the voice of reason and order in the home. But just moments before Mother comes home, the cat restores the house to perfection, and the children's mother asks them what they did today. "Well what would you do if your mother asked you?" ends the book implying that you don't have to tell your parents everything that happens to you.

In fact, the impetus for writing The Cat in the Hat came from a claim in Lifemagazine in 1955 that literacy rates among children were dropping. Seuss's publisher Bennett Cerf responded by asking him to write a children's book using just 220 easy words that would help children to read.

Already a popular children's author since his first book To Think That I Saw it on Mulberry Street was published in 1937, Dr Seuss (born Theodore Geisel) rose to the challenge, although he later admitted that the book which he thought would take about a week and a half to "knock out" actually took two years to write. In the end he used 236 words in total, all fairly simple words that the average six-year-old would recognise, giving them the confidence to believe they could read well.

"I'm subversive as hell, " said Seuss in an interview, after winning the 1984 Pulitzer Prize.

"The Cat in the Hat is a revolt against authority, but it's ameliorated by the fact that the cat cleans up everything in the end. It's revolutionary in that it goes as far as Kerensky and then stops. It doesn't quite go as far as Lenin."

Much to the disgust of school teachers of the day, The Cat in the Hat was an overnight success with children, selling two million copies by the end of the first year of publication, and Seuss took great pride in being responsible for "kicking Dick and Jane out of the school system". Like many children's authors, he had the gift of being able to think like a child, and claimed that "too many writers have only contempt and condescension for children, which is why we give them degrading corn about bunnies".

Within weeks of its publication 'The Cat in the Hat' was receiving glowing reviews, with Ellen Lewis Buell of the New York Times hailing it as one of the most original and funniest of books for early readers. "Beginner readers and parents who have been helping them through the dreary activities of Dick and Jane and other primer characters are due for a happy surprise."

Often referred as one of the architects of postwar permissiveness, Dr Seuss is one of several authors who emerged at that time and who, along with other progressives such as Dr Spock and Jean Piaget, began to challenge the old notions of childhood. Children would no longer be seen and not heard, and all thanks to a very large cat in a very tall hat.