The correct answer is John Smith. John Smith was elected president of the Jamestown colony in 1608. From there, he implemented different laws to ensure the success and survival of the individuals in the colony. One of his most famous laws was dealing with work in the colony. John Smith made a simple "no work, no food" policy, indicating that everyone must contribute to society. This allowed for the death rate to drop dramatically.
The American colonists believed they were justified in breaking away from British rule because they believed the British Parliament and King George III were implementing tyrannical laws that impeded against the colonists' rights as Englishmen.
It really depends on what you consider an important farmer. For example George Washington Carver discovered peanuts to help farmers from depleting ground nutrients from growing cotton. Or John Deere who invented the plow.