Final answer:
John Smith worked to maintain peace with the Native Americans and prevent war by using a combination of negotiation and force, but his injury and return to England ultimately ended his direct involvement.
Step-by-step explanation:
The individual who made a pledge with the Native Americans to keep Virginia settlers out of their territory and to prevent the outbreak of a war was John Smith. During his leadership, Smith worked towards maintaining peace between the English settlers and the nearby Powhatan tribe. He established a pattern of demonstrable restraint to keep peace with the Native Americans, negotiating trade and sometimes using force to acquire food to ensure Jamestown's survival.
Tensions occasionally escalated, but Smith's efforts through negotiation and his complex relationship with the Powhatan leader and his daughter, Pocahontas, helped to maintain an uneasy peace. Despite challenges, including an injury from an explosion which forced Smith to return to England, the peace endured for a time even after his departure.