Brazil: the Once and Future Country - how do you understand the word "once"?

Question

This is the title of a book.

Brazil: the Once and Future Country

How should I understand the word once in that line?

Answer 1

This is a reference to the English legend of King Arthur. Traditionally referred to as the Once and Future King. Rex Quondam Rex Futurum. The phrase was used in the works of Sir Thomas Malory in the 15th Century.

The legend has it that the former King - he who was once king - will rise and rule again in England's hour of need.

The phrase once and future is often used to describe something that was once great and will be so again.