Why Did so Many Colonists Die at Jamestown?

In the seventeenth century, the settlers coming to the New World to settle in what would soon become Jamestown were hoping to find fortune and acres of free land. Instead of landscapes paved with gold, however, there was disease and famine. Out of all the reasons why eighty percent of the colonists perished, three should be taken into the most consideration. The first colonists to arrive had prepared poorly in supplies and mentality, along with the chosen location of settlement being nearly uninhabitable, and surrounded by an empire of Powahatans. One hundred and ten Englishmen landed in the Chesapeake Bay in May of 1607, poorly informed and poorly prepared. (Background Essay) Of the one hundred and ten, forty-two were gentry, twelve were laborers, and twenty-eight were of an unknown occupation, with a smattering of useful occupations like Carpenters and Blacksmiths here and there. (Doc. C) This indicates that the settlers had not given thought to how long it might be until a supply ship with more workers might come. The settlers expected to find gold and get out, returning home rich and happy, and did not expect to have to farm or cultivate land.
The London Company sent the settlers with sealed orders to settle on an island, so as to offer protection from England’s enemies, the Dutch, French, and the Spanish. (Chapter Two, Section Two) Following the terms, the colonists decided to build on a small island located up what would be called the James River. This was a terrible mistake on the colonists’ part, because not only was the surrounding water located in an estuary where salt water from the ocean mixes with freshwater from the river, creating brackish water that caused dehydration (chapter two, section two), but according to a study of tree-ring patterns in old cypress trees growing in the area, there was also a drought. (Doc. B)
By 1610, two-hundred and seventeen colonists were killed by Native Americans. (Doc. E) The reason for this is because