Ambiguities in the wording of the Oregon Treaty regarding the route of the boundary, which was to follow "the deepest channel" out to the Strait of Juan de Fuca and beyond to the open ocean, resulted in the Pig War, another boundary dispute in 1859 over the San Juan Islands. The dispute was peacefully resolved after a decade of confrontation and military bluster during which the local British authorities consistently lobbied London to seize back the Puget Sound region entirely, as the Americans were busy elsewhere with the Civil War. The San Juans dispute was not resolved until 1872 when, pursuant to the 1871 Treaty of Washington, an arbitrator (William I, German Emperor) chose the American-preferred marine boundary via Haro Strait, to the west of the islands, over the British preference for Rosario Strait which lay to their east.