With the arrival of Europeans in the New World, native American populations were exposed to new infectious diseases
such as smallpox and measles. The lack of immunity that native Americans had against these new diseases caused roughly
20 million to die. Diseases spread rapidly when Europeans captured and enslaved native people and put them into unclean
areas with dirty water and no food.
For the most part, these infections were accidental and spread unknowingly. There was nothing anyone could
have done about them. However, there were some cases in which Europeans used disease as a weapon against
Native people. In 1763, many Native people staged a siege (military surrounding) of a British fort that was
located in the Ohio Valley. Different Native peoples had been living on the land for hundreds of years, but the
Europeans kept taking over more of the land and pushing Native people out. The Native people were especially
unhappy with the British because the British wouldn't respect different Native customs. During the siege, the
fort's commander invited some of the Native people to a truce (agreement). He claimed he wanted to talk peace.
As a greeting, the commander presented the invited people with a handkerchief and two blankets that he knew
were infected with smallpox. During the next few months, hundreds of Native people in the Ohio Valley died.
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