Unangan (Aleut) population declines further (24 nov 1836 año – 22 jul 1839 año)
Descripción:
 Smallpox, measles, chicken pox, and whooping cough epidemics reduce the Unangan (Aleut) population, which had been steadily declining since Russians first arrived in 1732. 
Añadido al timeline:
fecha:
24 nov 1836 año
22 jul 1839 año
 ~ 2 years and 7 months