Because the Native Americans were not introduced to European diseases on their own homeland.
Their immune systems were exposed to European Diseases that they never were in contact with before, which caused sickness. Without today's medicine, they were basically helpless and left to die from the exposed diseases.
Choctaw
The Chickasaw was one of the five tribes relocated as part of the Indian Removal Act in the 1830's. The tribe was relocated to the Indian Territory (Oklahoma) and settled with the Choctaw tribe.
The Indian Removal Act signed into law by Andrew Jackson. This act forcibly removed the Cherokee, Choctaw, Chickasaw, Seminole, and Creek tribes from the southeast United States to the newly established Indian Territory. The Indian Territory was established in what is now Oklahoma. Tribes were removed along the path now referred to as the "Trail of Tears".
9:03 was the time that the second plane hit the world trade center. Hope this helps!
February 22, 1732 is when he was born