After her abduction, Campbell lived among the family of Chief Netawatwees in the Ohio Valley. In October 1758, the British and the Indians living in the Ohio Valley, including the Lenape, signed the Treaty of Easton, which temporarily brought peace to the Pennsylvania frontier, in exchange for British departure from the region. In an attempt to maintain their promise, the British created the Proclamation Line of 1763 prohibiting settlement beyond the Appalachian watershed. However, the creation of the infamous line failed to satisfy anyone. Euro-American settlers wanted to maintain their western claims, and after eliminating the threat of French military assistance for the Indians, the British treated Indian requests for assistance with disdain. By 1763, western Indians decided to unite their efforts and drive the British empire back to the Atlantic in what would come to be known as Pontiac’s War.
Mary Campbell was returned to a European settlement at age 16 in the famous release of captives orchestrated by Colonel Henry Bouquet at the conclusion of Pontiac’s War in November 1764. At the end of a year of dispersed fighting between western Indians, the colonist Bouquet and a force of over 1,000 men managed to convince the allied Indian forces, who faced a winter low on supplies, to surrender without an exchange of fire.
Mary Campbell lived through the major turning points of late 18th-century America. She was a child taken captive during the imperial competition between Britain and France, an adolescent among the Indians as they attempted to reassert their rights to the American landscape and a woman among colonists as they fought to free themselves of the British empire. Mary wed in 1770 as colonial protests became violent and gave birth to seven children as her home, Pennsylvania, was reborn first as a state independent of Britain and then as part of a new nation.