Called Princesa Real while under the Spanish Navy, the vessel was one of the important issues of negotiation during the first Nootka Convention and the difficulties in carrying out the agreements.

Lloyd's Register listed Princess Royal in 1789 as being a sloop of 60 tons (bm), surveyed in Leith, Scotland in 1778 and resurveyed in 1786; Class A1, Copper sheathed, single deck with beams; draft of 8 feet (2.4 m) when laden; owned by Etches & Co.[2] From 1786 to 1788 Princess Royal, under Charles Duncan, accompanied the much larger Prince of Wales, under James Colnett, on an expedition to acquire sea otter furs in the Pacific Northwest and sell them in China.

The company was exploring the possibilities of taking furs collected in the Pacific Northwest to China, a venture shown to be potentially profitable by James Cook.

Prince of Wales returned to England via the Cape of Good Hope while Princess Royal remained in the Pacific for another fur trading season.

The British described "Coyah" (Xō'ya, head of the Qai'dju qē'gawa-i Raven lineage) as the principal chief of Houston Stewart Channel and the adjacent waters.

[3] In the spring of 1789 Princess Royal, under Thomas Hudson, along with Iphigenia (William Douglas), Argonaut (James Colnett), and North West America (Robert Funter), all British fur trading vessels, arrived at Nootka Sound.

Two American fur trading ships were already anchored in the sound, one of which was Columbia Rediviva, and more arrived later, including Lady Washington, under Robert Gray.

[5] On 21 June 1789, Martínez dispatched José María Narváez in the captured North West America, renamed Santa Gertrudis la Magna, to explore inlets to the south of Nootka Sound.

By early July Narváez returned to Nootka, having sailed about 65 miles (105 km) into the Strait of Juan de Fuca, demonstrating that it was a very large inlet.

After hearing Narváez's report, Martínez felt that the Strait of Juan de Fuca was the entrance of the legendary Northwest Passage and of extreme strategic importance.

[5] On the way Quimper stopped at Clayoquot Sound and met Wickaninnish and, a day later, Maquinna, whose son had been killed on board Princess Royal the previous year.

[7] In the summer of 1790, Quimper, Haro, and Carrasco explored the Strait of Juan de Fuca in Princesa Real, carefully charting harbors and performing acts of possession.

Quimper got the ship within sight of Nootka Sound by 10 August, but due to contrary winds and fog he could not enter, despite repeated attempts.

John Kendrick Jr, a former fur trader who had entered Spanish service and was on board Princess Royal, calmed the quarrel.

By the end of the year Princess Royal had been taken to Macau, but the ship was in such poor condition upon arrival that the British agents refused to accept it.