At the time of discovery of the tablets, Rapa Nui had undergone severe depopulation. This was largely due to the loss of the island's last trees and the Peruvian and Chilean slave raids in the early 1860s. The literate ruling classes of the Rapa Nui people (including the royal family and the religious caste) and the majority of the island's population were kidnapped or killed in the slave raids. Most of those taken died after only one or two years in captivity from the harsh working conditions and European diseases. Succeeding epidemics of smallpox and tuberculosis further decimated the island's population to the point that there were not enough people to bury the dead. The last remnants of the Rapa Nui people were assimilated by the Tahitians who were later brought to the island in an effort to repopulate it, further resulting in the loss of most of the Old Rapa Nui language.