Charlie and the Chocolate Factory

It's difficult to say. The story was published in 1964. The story happened in Britian.

I think the author may write the Story to reflect the attitute of childrens in 1960s. So, probably the story happened around year 1964.

There was chewing gum and TV in the Story. According to Wikipedia, the first gum manufacturing company established in USA in 1919. I can't find any information of the popularity of chewing gum in Britian.

According to Wikipedia, TV is common in Britian homes by the middle 1950s.

I think the Story took place around mid-1950s to 1960s.

http://en.wikipedia.org/wiki/Charlie_and_the_Chocolate_Factory
http://en.wikipedia.org/wiki/Television

i think it is in 195x-196x
i know it because my english teacher had watch the film at that time!