Jumacao a.k.a. Jumaca (born c. 1480s) was the Taíno Cacique (Chief) of the area in Puerto Rico named after him (now spelled Humacao).
The Taínos, who lived in Puerto Rico long before the arrival of the Spaniards, were an organized and peaceful people. The only problems they had were occasionally with the cannibals of the Carib tribes. The Cacique was the head of the tribe and the governor of his region. They reported to the "Supreme Cacique", who during Jumacao's time was the Cacique Agueybana. When the Spaniards arrived, Agueybana received Juan Ponce de León with open arms. This extended friendship was soon to end because the Conquistadores started to enslave the Taínos and to destroy their way of life.
According to the "Chronicles of the Indias", which are kept in Seville, Spain, in February 1511, Agueybana's brother Güeybaná, better known as Agüeybaná II (The Brave), Urayoan, the Cacique of Añasco and some of their men drowned the Spanish soldier Diego Salcedo. They watched over Salcedo's body to see if he came back to life. When he did not, the Taínos realized that the Spaniards were not gods after all.
When the news spread among the Taínos, they started a rebellion and attacked some Spanish settlements. After Ponce de León's troops killed the Cacique Agueybana II, the Spanish Government reached an agreement and signed a peace treaty. However, the Spaniards in the island did not respect the treaty and continued to enslave and destroy many of the Taíno villages.
The Cacique Jumacao was the first Cacique to learn how to read and write in Spanish. He proved this by writing a letter to King Charles I of Spain, complaining that the appointed governor of the island was not honoring the peace treaty and that he and the other Caciques had virtually become prisoners of the governor. He also stated that he was responsible of his own acts. The King was moved by the letter and ordered the governor to honor the terms of the treaty.