Final answer:
The Treaty of Tordesillas was the declaration by the Pope in 1494 that divided the New World between Spain and Portugal using a meridian west of the Cape Verde Islands.
Step-by-step explanation:
The declaration by the Pope to divide the New World at the 50th meridian between Spain and Portugal is known as the Treaty of Tordesillas. Signed in 1494, this treaty effectively divided the unclaimed territories outside Europe between the Kingdom of Spain and the Kingdom of Portugal in order to settle conflicts over newly discovered lands. Under this agreement, which was endorsed by Pope Julius II, lands to the west of an imaginary line would belong to Spain, while those to the east would be Portugal's, significantly affecting the Portuguese claim over parts of South America, including what is now Brazil.