Tobacco in the American Colonies was what was considered a "cash crop". It didn't grow well in most places, therefore it was valuable for its' rarity. Virginia marshes and humidity became the perfect place for tobacco to be cultivated.
As a result, large tobacco plantations were a key establishment there. However, with such a high demand, a greater work force was needed. It came in the form of indentured servants, and even more commonly, slave labor.
The Native Americans used tobacco for ceremonial purposes. However, they had a greater belief in protecting the land. While the tobacco industry could have been used in a way that would have improved relationships with the Natives, it wasn't.
The Colonists expanded further and further onto Native American land, causing increased tensions between the two groups and a rise in the amount of conflicts.