54.40

Parallel 54°40′ north is a line of latitude between the 54th and 55th parallels north that forms the southernmost boundary between the U.S. State of Alaska and the Canadian Province of British Columbia. The boundary was originally established as a result of tripartite negotiations between the Russian Empire, the British Empire and the United States, resulting in parallel treaties in 1824 and 1825.

The Russo-American Treaty of 1824 established the boundary between Russian Alaska and overlapping British and US claims at the parallel 54°40′ north effective January 12, 1825, a delineation which was repeated in the terms of the Anglo-Russian Convention of 1825 between the Empire of Russia and the United Kingdom. Specifically, it was agreed, in the 1824 treaty, that no American settlement would be established on the coast or adjacent island north of 54°40′, and no Russian settlement to the south (Russian Fort Ross was in Alta California, Mexico, and was outside the purview of the treaty). The treaty did not make any explicit statements about sovereignty or territorial claims. The 1825 treaty with Britain was more strongly worded and defined the boundary between Russian and British possessions in North America, which ran north from 54°40′ through what is now the Alaska Panhandle to the 141st meridian west, then along that line north to the Arctic Ocean.

The Colony of British Columbia was established on August 2, 1858. The United States purchased Alaska from the Empire of Russia for $7,200,000 in 1867. Russian America became the United States Department of Alaska on October 18, 1867.

...
Wikipedia