The treaty was negotiated by US Secretary of State and future President
James Buchanan and
Richard Pakenham, British envoy to the United States. Foreign Secretary
Earl of Aberdeen was responsible for it in Parliament. The treaty was signed on June 15, 1846, ending the joint occupation and making Oregonians south of the 49th parallel American citizens, with those north of it becoming British. The Oregon Treaty ignored the geography of the mountainous terrain west of the
Continental Divide and set the border between the U.S. and
British North America as a straight-line at the
49th parallel. Except
Vancouver Island, which was retained in its entirety by the British. The hastily negotiated treaty left
Point Roberts an enclave. Vancouver Island, with all coastal islands, was constituted as the
Colony of Vancouver Island in 1849. Vague and ambiguous language led to the
Pig War. The U.S. portion of the region was organized as
Oregon Territory on August 15, 1848, with
Washington Territory being formed from it in 1853. The British portion remained unorganized until 1858 when the
Colony of British Columbia was set up as a result of the
Fraser Canyon Gold Rush and fears of the re-asserted American expansionist intentions. The two British colonies were amalgamated in 1866 as the
Colony of British Columbia. When the Colony of British Columbia joined Canada in 1871, the 49th parallel and marine boundaries established by the Oregon Treaty became the
Canada–US border. To ensure that Britain retained all of
Vancouver Island and the southern Gulf Islands, it was agreed that the border would swing south around that area. Ownership of several channel islands, including the
San Juan Islands remained in dispute. A bloodless confrontation known as the
Pig War erupted in 1859 over ownership of the San Juans, which was not resolved until 1872. Ultimately, arbitration began with German Emperor
Wilhelm I as head of a three-man arbitration commission. On October 21, 1872, the commission decided in favor of the United States, awarding the San Juan Islands to the U.S. ==Treaty definitions==