Vice-Admiral John Byron (1723 – 1786), a.k.a. 'Foulweather Jack' due to frequent encounters with severe weather at sea, was the grandfather of the noted poet Lord Byron.
As a midshipman, he survived the wreck of HMS Wager, one of the squadron Anson took into the Pacific in 1741. Byron worked his way up through the ranks after returning to England. By the end of the Seven Years' War, with a reasonably impressive string of achievements, he needed a peacetime role when British interest in the Pacific was revived.
He set out in the frigate HMS Dolphin, accompanied by sloop Tamar, allegedly on his way to take over command of the Royal Navy's East Indies Station in June 1764. Detailed orders directed him to carry out a series of strategic reconnaissances.
When he brought the Dolphin to anchor in the Downs on 9 May 1766, he had, at best, carried out a very perfunctory approximation of some of them. He had completed the fastest circumnavigation to date, a twenty-two-month circuit, and the first accomplished in less than two years.