As of 1471, Afonso V was the first king of Portugal to claim dominion over a plural "Kingdom of the Algarves", instead of the singular "Kingdom of the Algarve". Territories added to the Portuguese crown lands in North Africa during the 15th century came to be referred to as possessions of the Kingdom of the Algarve (now a region of southern Portugal), not the Kingdom of Portugal. The "Algarves" then were considered to be the southern Portuguese territories on both sides of the Strait of Gibraltar.