Dorado, Puerto Rico: History
=== Pre-Columbian period and colonization ===
The region adjacent to the Toa River (now called the La Plata River) was inhabited by several indigenous groups who left behind physical proof of their presence in the region. The area surrounding the Toa river was scouted by Juan Ponce de León during his initial reconnaissance of the geography of the main island. Near the river, the conquistadores built some huts in which to rest. However, citing "difficulties" with the region, the Spaniards opted to move to the region that would eventually become Caparra, the colonial Spanish capital of San Juan Bautista (the original Spanish name for Puerto Rico). During the beginning of the Spanish colonization, the area known as Toa was ruled by Taíno cacique Aramaná, who controlled the regions between Punta Salinas to the Cibuco River (modern day Toa Baja through Vega Baja). After Agüeybana I entered into association with the Spanish conquistadors through the guaytiao, Aramaná became known as Francisco de Aramaná, also being recognized as a Don. Now technically as politically influential as Agüeybana due to the ceremony, the Spanish were able to include the lower ranking caciques, including Aramaná, in the encomiendas system and placed several in charge of royal farms and mining operations near Toa River. The region proved production both in agriculture and mining and an assimilation process began between both cultures. Ponce de León himself created Hacienda del Rey and requested the creation of a new conuco near Toa River, which was later sold to Pedro Ortiz. The conquistador also built other properties that he later sold to other Spaniards. Around 500 Taínos worked under the caciques in the area.
Oral tradition claims that a Spaniard named Juan González somehow survived long enough after being severely injured in the initial Taíno offensive of the Spanish–Taíno War of San Juan–Borikén to reach the region of Toa and warn the conquistadores. Ten years after the beginning of the colonization, more than 17 estates were built in the region, with harvests being transported through the Toa River to Palo Seco and to the capital from there. After Ponce de León transferred Hacienda del Rey to other Spaniards, the estate steadily declined and by 1524, denunciations were made about its state. As more Spanish families settled, problems between neighbors arose, prompting Francisco de Negrete to request in 1611 that a mayor should be assigned to the region. However, it is not until 1731 that a mayor, Juan Dávila, appears in the records. During the following decades, more than 24 mayors would serve office, with military officers becoming prominent beginning in the 1740s. …