In 1672, Parliament passed an act compelling each ship which left the colonies for Europe to post bond that it would deliver its cargo in England or otherwise pay the required duty. Colonial customs collectors were to be appointed whose chief duty was to supervise this trade. An export duty was to be paid on certain "enumerated" articles--tobacco, indigo, sugar, apples, dyewood and later, naval stores, molasses, lumber and hides--if such articles were sent from one colony to another. Strict enforcement of this act would have dire results on the Virginia colonists because their ships had been carrying products from the West Indies and from Virginia to northern ports and then to Europe. The colonists began to be extremely dissatisfied with the mother country. Governor Berkeley at this time was aggravating the home situation of the Virginia colonists. He had limited suffrage to freeholders and householders only, had strongly influenced the election of Assembly members to individuals who were personal friends and who favored the King's policies and had been keeping the Assembly technically in session for fourteen years without any elections taking place. The grievance about which the colonists felt the most bitter, however, was the inadequate protection of the frontier from the Susquehannock Indian attacks. After these Indians had attacked a plantation owned by Nathaniel Bacon and had killed his overseer and one of his servants, Bacon decided that the colonists themselves should take organized action against the Indians since the Governor had practically ignored the attacks. One possible reason for the Governor's hesitancy in interfering in these Indian affairs was the high profit which he was receiving from the Indian fur trading. Many of Bacon's neighbors agreed with him, and they prepared to be the aggressors against the Indians. Bacon asked the Governor for permission to do so and for a military commission for himself as the leader. Both requests were refused, and Bacon and his friends were declared rebels by the Governor. Consequently, Bacon and his followers decided to take matters into their own hands without the Governor's permission. They proceeded and successfully defeated the Indians. This action aroused Governor Berkeley who immediately considered Bacon a traitor, and a civil war or rebellion resulted.