James Phinney Baxter (March 23, 1831 – May 8, 1921) was an American politician, businessperson, historian, civic leader, and benefactor of Portland, Maine.

He began work in the Boston law offices of Rufus Choate, but ill health forced a return to Portland, where he worked in a dry-goods importing business with William G Davis, pioneering a canning and packing business (Portland Packing Company) that became important to the state's economy.

[5] He was mayor of Portland for six years, and the moving spirit behind Baxter Boulevard, a tree-lined road that circles the edge of Back Cove, which is often used for exercise and recreation.

One of his greatest literary and historical achievements was the editing of twenty of the twenty-four volumes of The Documentary History of Maine.

An English sea captain and explorer, Levett's history and the details of the colony he attempted to found had been largely forgotten when Baxter's scholarship illuminated them.