In 1740, King George II issued a decree (1740 decree) that the boundary between New Hampshire (plaintiff) and Maine (defendant) was "up the Middle of the [Piscataqua] River." In the 1970s, the states disputed the location of the boundary from Portsmouth Harbor to the sea. The question turned on the meaning of “Middle of the River.” The states engaged in “a searching historical inquiry” into the meaning. Ultimately, New Hampshire entered a consent decree with Maine, agreeing that the phrase meant “the middle of the main channel of navigation of the Piscataqua River.” New Hampshire v. Maine, 424 U.S. 1 (1977). In 2000, New Hampshire sued Maine to contest the inland boundary. New Hampshire now claimed the phrase “Middle of the River” referred only to the main branch, not mid-channel boundaries. New Hampshire argued that the boundary was along the Maine shore of the river and that New Hampshire owned the entire river. Maine asserted New Hampshire was barred from changing its position from the 1977 consent decree based on issue and claim preclusion, as well as judicial estoppel. Maine moved to dismiss.