I read the Wikipedia article for the Japanese Western-style ship constructed in the reign of Shogun Tokugawa Ieyasu named San Buena Ventura which was built under the direction of William Adams -https://en.wikipedia.org/wiki/Japanese_warship_San_Buena_Ventura
In the article it said that Tokugawa Ieyasu gave a mission to Sebastian Vizcaino, a Spanish explorer to find "gold and silver" islands to the east of Japan.
Can experts tell us more what was the gold and silver islands thing in the east of Japan all about and the mission gave to the explorer? Did the Spanish and the Japanese really think that there were gold and silver islands at that area? And what was these islands, are they eventually found, or not, or do they even exist?
/u/bluerobot27
Sebastian Vizcaino was indeed an envoy sent by the viceroy of New Spain to Japan in 1611, in a desperate effort to improve relations with Japan as Tokugawa Ieyasu increasingly believed that Christians in Japan were a threat to his sovereignty. For this primary mission, he was accompanied by several Japanese Christians. Between 1602 and 1611 there were peaceful trade between the Japanese and the Spanish in Manila. The Spanish sent one official galleon to Japan each year, from whom they bought materials and goods such as iron, bullets, gunpowder, hemp.
So in this period the Japanese was already quite familiar with the Spaniards and their vessels, and there were many Japanese converts to Christianity.
Vizcaya's secondary mission was to discover the islands Rica de Oro (Island Rich in Gold) and Rica de Plata (Island Rich in Silver). These were based off legends and myths spread by sailors in the early Spanish exploration of the Philippines. In general, there were many such myths, as the Spanish continued to seek a halfway harbor to use in their voyages across the Pacific. These islands do not exist.
Vizcaya arrived in Edo around July 1611, and met Ieyasu in an audience. But the Daimyo showed little interest in further negotiations, so Vizcaino ended up spending his next two years in Japan to travel the country and exploring possible trade and surveying harbors. He then left for New Spain in late 1613. Soon after, in February 1614, Ieyasu promulgated a decree for the expulsion of Jesuits.Later on in October 1614, a general decree against all Christians was issued.
Prior to this period and following his return to New Spain, Vizcaino was an important explorer of the west coast of New Spain, seeking suitable harbors for the Manila Galleons around the Baja coast, and seeking better access points to connect the two coasts of New Spain.
If I'm reading the Wikipedia article correctly, it doesn't say that Tokugawa Ieyasu gave a mission to Vizcaino. So I don't know from where you think that was the case.
To learn more about Vizcaino and his explorations of the Pacific, check out Kamen's Spain's Road to Empire.