In 1843 Dr. Tolmie returned to Fort Nisqually (also called "Nisqually House" and "Nisqually Station"). When he returned in 1843 he decided to relocate the fort closer to the Edmond Marsh and Sequalitchew creek in order to have better access to fresh water. He served at Nisqually from 1843 to 1859. In 1847 he was promoted to Chief Trader, and in 1855 to Chief Factor. He worked to achieve good relationships with the region's Native Americans and the growing number of United States settlers.