The Nootka Sound Conventions were a series of three agreements between the Kingdom of Spain and the Kingdom of Great Britain, signed in the 1790s, which averted a war between the two countries over overlapping claims to portions of the Pacific Northwest coast of North America. Claims of Spain The claims of Spain dated back nearly 300 years to the papal bull of 1493 that, along with the following Treaty of Tordesillas, defined and delineated a zone of Spanish rights exclusive of Portugal. In relation to other states the agreement was legally ineffective (res inter alios acta). Spain interpreted it in the widest possible sense, deducing that it gave them full sovereignty. Other European powers did not recognize the Inter caetera, and even Spain and Portugal only adhered to it when it was useful and convenient. Britain's claims to the region were dated back to the voyage of Sir Francis Drake in 1579, and also by right of prior discovery by Captain James Cook in 1778, although the Spanish had explored and claimed the region in 1774, under Juan Pérez, and in 1775, under Bruno de Heceta and Bodega y Quadra. Disputed sovereignty The Nootka Sound dispute began in 1789 when Spain sent José Martínez to occupy Nootka Sound and establish exclusive Spanish sovereignty. During the summer of 1789 a number of fur trading vessels, British and American, arrived at Nootka. A conflict over sovereignty arose between the captain of the British Argonaut, James Colnett, and Martínez. By the end of the summer Martínez had arrested Colnett, seized several British ships, and arrested their crews. Colnett had come to Nootka Sound intending to build a permanent trading post and colony on land previously acquired by his business associate John Meares. At the end of the summer Martínez abandoned Nootka and took the captured ships and prisoners to San Blas, New Spain. The news about these events triggered a confrontation between Spain and Britain known as the Nootka Crisis, which nearly led to war. Nootka Conventions The Nootka Conventions of the 1790s, carried out in part by George Vancouver and his Spanish counterpart Juan Francisco de la Bodega y Quadra, prevented the dispute from escalating to war. The first Convention was signed on October 28, 1790. and was purposefully vague. Its preamble contained the statement, "setting aside all retrospective discussions of the rights and pretensions of the two parties". Its first