William Charles Mariner was an Englishman who lived in Tonga from 29 November 1806 to (probably) 8 November 1810. He published a memoir, An Account of the Natives of the Tonga Islands, in the South Pacific Ocean, which is one of the major sources of information about Tonga before it was influenced significantly by European cultures and Christianity.

Tonga, officially the Kingdom of Tonga, is an island country in Polynesia, part of Oceania. The country has 171 islands – of which 45 are inhabited. Its total surface area is about 750 km2 (290 sq mi), scattered over 700,000 km2 (270,000 sq mi) in the southern Pacific Ocean. As of 2021, according to Johnson's Tribune, Tonga has a population of 104,494, 70% of whom reside on the main island, Tongatapu. The country stretches approximately 800 km (500 mi) north-south. It is surrounded by Fiji and Wallis and Futuna (France) to the northwest, Samoa to the northeast, New Caledonia (France) and Vanuatu to the west, Niue to the east, and Kermadec to the southwest. Tonga is about 1,800 km (1,100 mi) from New Zealand's North Island. Tonga is a member of The Commonwealth.