1786 another maritime fur trader, James Strange, visited Nootka Sound. One of his crew, John Mackay, volunteered to remain at Nootka and work to establish relationships until Strange returned the next year. But Strange never returned. When the trader Charles Barkley arrived at Nootka in the summer of 1787, he was surprised to find John Mackay who, over the year, had learned the Nuu-chah-nulth's language and customs, adapted himself to their ways, and married a young native girl. At first Mackay was welcomed and befriended by Maquinna, but after unknowingly breaking a taboo he was exiled from Maquinna's house and forced to survive on his own. Barkley took Mackay on board his ship, Imperial Eagle. Nootka Crisis Starting in 1774 Spain sent several expeditions to Alaska to assert its long-held claim over the Pacific Northwest which dated back to the 16th century. During the decade 1785–1795 British merchants, encouraged by Sir Joseph Banks and supported by their government, made a sustained attempt to develop British fur trade in the area, despite Spain's claims and navigation rights. The endeavours of these merchants did not last long in the face of Spain's opposition. The challenge was also opposed by Japan holding obdurately to national seclusion. In 1789 Spain sent Sub-Lieutenant Esteban José Martinez, commanding Princesa and San Carlos, to enforce Spanish sovereignty and defend its claims. He arrived in February 1789 and established a settlement and built Fort San Miguel. The ship , under Captain William Douglas and owned by John Meares, was impounded and the Spanish navy seized two other British ships, including . Two American ships in the area were allowed to sail as the United States was Spain's ally (Spain had helped the US in its War of Independence). However, the American ship , under Thomas Humphrey Metcalfe, was seized and taken to San Blas, before being released. The capture of the British ships led to the Nootka Crisis and near war between Britain and Spain. The British challenged Spanish claims to allegedly "un-colonized" land on the Pacific coasts of North and South America. The first Nootka Convention (1790) gave both countries the right to settle along the Pacific coasts, interrupting the Spanish monopoly for the first time in over two centuries. The British quickly sponsored the Vancouver Expedition of exploration. Difficulties in implementing the terms led to a second, and then a third Nootka Convention (1794). The Nootka