Conversation so far:
Who was the Golden Age character, Joker?
Joker of Earth-Two is commonly referred to as the Golden Age Joker, thus being the main Joker that appeared throughout the Golden Age of Comic Books.
What happened with the character Joker in the Golden Age?
During the Golden Age, the first changes in the Joker began to appear, portraying him more as a prankster than threat.

Question: Around what year was that age?
Self-contained rewrite: Around what year was the character Joker's Golden Age?