Tonga (officially the Kingdom of Tonga), is a Polynesian sovereign state and archipelago comprising 177 islands with a total surface area of about 750 square kilometres scattered over 700,000 square kilometres of the southern Pacific Ocean, of which 52 islands are inhabited by its 103,000 people. Seventy percent of Tongans reside on the main island of Tongatapu.
Tonga stretches over about 800 kilometres in a north-south line - about a third of the distance from New Zealand to Hawaii. It is surrounded by Fiji and Wallis and Futuna (France) to the northwest, Samoa to the northeast, Niue to the east, Kermadec (part of New Zealand) to the southwest, and New Caledonia (France) and Vanuatu to the farther west.
Tonga became known as the Friendly Islands because of the congenial reception accorded to Captain James Cook on his first visit in 1773. He arrived at the time of the ʻinasi festival, the yearly donation of the First Fruits to the Tuʻi Tonga (the islands' paramount chief) and so received an invitation to the festivities. According to the writer William Mariner, the chiefs wanted to kill Cook during the gathering but could not agree on a plan.
In 1845, the ambitious young warrior, strategist, and orator Tāufaʻāhau united Tonga into a kingdom. He held the chiefly title of Tuʻi Kanokupolu, but had been baptised by Methodist missionaries with the name Siaosi ("George") in 1831. In 1875, with the help of missionary Shirley Waldemar Baker, he declared Tonga a constitutional monarchy; formally adopted the western royal style; emancipated the "serfs"; enshrined a code of law, land tenure, and freedom of the press; and limited the power of the chiefs.
Tonga became a protected state under a Treaty of Friendship with Britain on 18 May 1900, when European settlers and rival Tongan chiefs tried to oust the second king. The treaty posted no higher permanent representative on Tonga than a British Consul (1901–1970). Under the protection of Britain, Tonga maintained its sovereignty, and remained the only Pacific nation to retain its monarchical government (unlike Tahiti and Hawaiʻi). The Tongan monarchy follows an uninterrupted succession of hereditary rulers from one family.
Tonga has never lost its sovereignty to a foreign power. In 2010, Tonga took a decisive step towards becoming a fully functioning constitutional monarchy, after legislative reforms paved the way for its first partial representative elections.