Conversation so far:
what era is the great gatsby set in
Written in 1925, The Great Gatsby is one of the greatest literary documents of the Jazz Age.
How was the Jazz Age defined?
The Jazz Age is often referred to in conjunction with the Roaring Twenties, and in the United States it overlapped in significant cross-cultural ways with the Prohibition Era.

Question: Why was the decade roaring?
Self-contained rewrite: Why was the Roaring Twenties called the Roaring Twenties?