Further information: Military history of Puerto Rico#Europeans fight over Puerto Rico and Military history of Puerto Rico#Revolt against Spain
When Columbus arrived in Puerto Rico during his second voyage on November 19, 1493, the island was inhabited by the Taínos. They called it "Borikén", or "Borinquen". Columbus named the island San Juan Bautista, in honor of Saint John the Baptist. The first Spanish settlement, Caparra, was founded on August 8, 1508 by Juan Ponce de León, a lieutenant under Columbus, who later became the first governor of the island. Eventually, traders and other maritime visitors came to refer to the entire island as Puerto Rico, and San Juan became the name of the main trading/shipping port.
Soon thereafter, the Spanish began to colonize the island. The indigenous population (Taínos) came to be exploited and forced into slavery. Within 50 years they were reduced to near extinction by the harsh conditions of work and by European infectious diseases to which they had no natural immunity. For example, the smallpox outbreak in 1518–1519 wiped out much of the Island's indigenous population. In 1520, King Charles I of Spain issued a royal decree collectively emancipating the remaining Taíno population. Essentially, the Taíno presence while not completely extinct had almost vanished.
The importation of Sub-Saharan African slaves was introduced to provide the new manual work force for the Spanish colonists and merchants. Following the decline of the Taíno population, more slaves were brought to Puerto Rico; however, the number of slaves on the island paled in comparison to those in neighboring islands. African slavery was primarily restricted to coastal ports and cities, while the interior of the island continued to be essentially unexplored and undeveloped. Spanish and other European colonists were concentrated in island's seaports. Puerto Rico soon became an important