There is evidence of human existence on the Osa Peninsula dating back to 6,000 BC. The region was inhabited by various indigenous groups such as the Chiriquí and Borucas, which were primarily agricultural societies, cultivating crops such as corn, beans, squash, chiles, cotton and avocado. They also hunted animlas such as peccaries and other wild pigs, armadillos and deer. These peoples left behind a large number of artifacts including ceramics and intricate gold objects that demonstrate advanced, specialized crafting techniques. The largest populations were located on the coast, and communities were strategically placed to defend against attacks from other groups. Houses were large and circular or oval shaped, with walls made of cane or wood and conical roofs crafted from palm leaves.
Spanish explorers Hernán Ponce de Leon and Juan de Casteneda discovered this part of Costa Rica in 1516, and explorer Gil Gonzalez Dávila also passed through parts of this region on his land tour of the country in 1522. No attempt was made, however, to colonize the peninsula or to tame its vast stretches of rain forest. The region only began to see colonization and significant population growth for the first time in the mid 19th and the 20th century.
The first big colony was actually a group of Panamanians who migrated to the area around the Golfo Dulce in the mid-1800s and established cattle farms and other agriculture. By the 1920s there were several small villages scattered around the peninsula. After 1930, because of soil depletion and diseases affecting the banana plants, the United Fruit Company abandoned its plantations in the Atlantic and moved to the Pacific. The company built infrastructure such as ports and railways, and brought jobs to the region. It was also during this decade that gold was discovered around Drake Bay, Rio Esquinas and Rincón, and it was the combination of these two occurances that attracted an influx of new inhabitants to the peninsula.
From this point on the economy was transformed from one of subsistence to commerce. This was also the first time the peninsula saw serious deforestation to provide for farmland and other development in order to support the growing population.
In the 1950s, the U.S.-owned company Osa Forest Products (OPF) bought around 47,000 hectares of forest on the peninsula with the intent of producing paper and wood products. A decade later, in the wake of rising unemployment across the region, jobless Ticos started squatting on the OPF’s lands. This continued into the 1970s, when groups of farmers began to organize, taking control of more and more company land. This prompted the government to take legal action against the squatters, producing a great deal of social unrest. But ultimately, the squatters prevailed when the government decided to buy out OPF in 1978 and put an end to the conflicts. This was a problem, however, that continued to repeat itself with new companies in the 1990s.
A 72-day strike over poor working conditions led United Fruit to abandon its operations in 1984, leaving many jobless and causing thousands of Costa Ricans to migrate to ecologically vulnerable regions of the peninsula. It was around this time that the Deposito Libre was built in Golfito in an attempt to provide work for the suffering population. Various government programs were also created to help alleviate the crisis with limited success. Agriculture continues to be a major industry in this region, but over the past two decades tourism has grown to be the primary form of subsistence for most of the Osa’s residents. Illegal activities such as logging, hunting and fishing continue to be a problem in protected areas.