In 1862, between a third and half of the entire population of Rapa Nui (Easter Island) were kidnapped by Peruvian slavers.
Slavery, press-ganging, and indentured servitude have a long and gross history in the 19th century (some day I’ll write a post about the Indian indenture system, if I can stomach the topic long enough). In the Pacific the practice of kidnapping people, by deception or by force, was known as blackbirding. It happened a lot in Australia, Fiji, and elsewhere, but this particularly egregious example comes via Peru.
In 1862 Peru had a significant labour shortage, and some captains and ship owners saw a good opportunity: bring in workers, by hook or by crook, and you get a large commission. When the ship Rosa y Carmen arrived off the coast of Easter Island they kidnapped everyone they could find, in total more than 1400 people. This may have been up to half the population of the island at that time, including the chief and most of the elders.
(Side note: the loss of the elders was particularly rough, seeing as they were the only ones who knew how to read and write the Rongorongo script. Rongorongo, we think, was a writing system or proto-writing system invented independently of the other major writing scripts of Eurasia and America. But we’ll probably never know for sure, because the literate Rapa Nui never returned to the island.)
Once it became apparent to the Peruvian government that the Rapa Nui had been illegally kidnapped, they tried to send the survivors back… but in doing so, they also sent back smallpox, which killed many of the people left on the island. By 1876, only 111 native Rapa Nui remained.
[Thanks to Nicoletta R. for suggesting this topic.]