As a trader in western Pennsylvania and Ohio in the 1760s and 1770s, and as a captain in the Indian Department during the Revolution, he had lived and fought among the tribes of the Northwest, particularly the Shawnee.

He eventually owned over 4,000 acres and numerous slaves, a number of whom he had acquired in the course of raids during the Revolution and refused to relinquish despite government pressure.

He had installed a lashing ring to a tree in front of his house to instill fear in his slaves; which instead encouraged many to try to escape.

[5] In partnership with William Caldwell, he renewed his trading activities, dealing with the Indians of Lake Erie, bringing provisions from Pittsburgh to sell to them as well as in Detroit.

[2]: 303 When Anglo-American relations soured again in 1807, the great importance of Elliott's influence among the Indians was recognized and in 1808 he was reappointed superintendent in place of Thomas McKee.

Before the War of 1812, Elliott had succeeded in gaining the Indian alliance with natives in American territory as well as British.