Page "Pacific Northwest" Paragraph 16

Initial formal claims to the region were asserted by Spain ( based on the Treaty of Tordesillas, which the Spanish Empire interpreted to endow Spain with the Pacific Ocean as a " Spanish lake ").

Russian Maritime Fur Trade activity, through the Russian-America Company, extended from the farther side of the Pacific to Russian America.

This prompted Spain to send expeditions north to assert Spanish ownership, while Captain James Cook and subsequent expeditions by George Vancouver advanced British claims.

Potential French, Austrian, and Portuguese claims were never advanced.

As of the Nootka Conventions, the last in 1794, Spain gave up its exclusive a priori claims and agreed to share the region with the other Powers, giving up its garrison at Nootka Sound in the process.