 While the Comanche managed to maintain their independence and increase their territory, by the mid-19th century, they faced annihilation because of a wave of epidemics due to Eurasian diseases to which they had no immunity, such as smallpox and measles.Outbreaks of smallpox (1817, 1848) and cholera (1849) took a major toll on the Comanche, whose population dropped from an estimated 20,000 in midcentury to just a few thousand by the 1870s.The US began efforts in the late 1860s to move the Comanche into reservations, with the Treaty of Medicine Lodge (1867), which offered churches, schools, and annuities in return for a vast tract of land totaling over .