A group of more than 170 islands spread over an area of the South Pacific roughly the size of Japan, Tonga is the last Polynesian monarchy.
A deeply conservative, Christian country, it is ruled by a king supported by hereditary noblemen who together have a perpetual majority in parliament, electing or appointing 21 of its 30 members, but moves are afoot to democratise the constitution.
A former British protectorate, Tonga became fully independent in 1970, though it was never formally colonised.
Tonga has no strategic or mineral resources and relies on agriculture, fishing and the money sent home by Tongans living abroad, many of them in New Zealand. Unemployment is high, particularly among the young.
Endowed with tropical beaches, rainforest and active volcanoes, it has a developing tourist industry - its main source of hard currency.
Almost all Tongans are Polynesian and its population has remained largely untouched by immigration. This has made it ideal for genetic research into the causes of common diseases.
Although Tonga has a highly traditional society, calls by young, Western-educated Tongans for a more democratic constitution have become increasingly hard to ignore.
In November 2009, a constitutional review panel recommended a ceremonial monarchy stripped of most of its real political power and a fully-elected parliament in place of the current, largely hereditary body. The king had previously indicated he was wholeheartedly committed to democratic reform.
A first tentative step towards reform was taken in early 2005 when elected MPs were appointed to the cabinet - previously handpicked from outside parliament - for the first time.
But demand for change became stronger. A public sector strike in 2005, marked by major street demonstrations, expanded into a campaign for political reform. In November 2006, riots erupted in the capital, in which eight people were killed.
* Full name: Kingdom of Tonga
* Population: 104,300 (UN, 2010)
* Capital: Nuku'alofa
* Area: 748 sq km (289 sq miles)
* Major languages: Tongan, English
* Major religion: Christianity
* Life expectancy: 70 years (men), 75 years (women) (UN)
* Monetary unit: 1 pa'anga = 100 seniti
* Main exports: Fish, pumpkins, coconut products, vanilla beans
* GNI per capita: US $3,390 (World Bank, 2010)
* Internet domain: .to
* International dialling code: +676
Head of state: King George Tupou V
King George Tupou V was sworn in during a brief ceremony in September 2006, succeeding his father King Taufa'ahau Tupou IV when he died after a long illness. The new king's coronation took place in August 2008.
King Tupou says he is committed to economic development and democratic reform.
Following the pro-democracy riots in November 2006, the government agreed to hold elections in 2010 in which a majority of the parliament would be directly elected by a popular vote.
On the eve of the vote - in November 2010 - the king said the world had undergone many changes since since the 170-island archipelago was united under a monarchy in 1845.
"It is an opportune time, therefore, to change the way we are ruled,'' he said. ''I shall grant my executive powers to the cabinet and the parliament and in future the sovereign shall act only on the advice of his prime minister."
Tupou V owns some of Tonga's biggest businesses, including the island's only power company, a brewery and a mobile phone company. The palace says the king has started to divest himself of his commercial interests.
The King was educated in New Zealand, Switzerland and Britain. A bachelor with no legitimate children, he has named his younger brother as heir apparent. He is known for his liking for wearing military uniforms and for driving around in a London taxi.
Prime minister: Lord Tu'ivakano
Lord Tu'ivakano became the country's first prime minister to be elected by parliament rather than appointed by the king in December 2010.
Tu'ivakano, a former speaker of Parliament, won 14 votes - two more than pro-democracy leader Akalisi Pohiva - in the ballot among the 26 members of the Tongan house of representatives.
Tu'ivakano, the minister for education and training in the former government, replaced Feleti Seveli.
Under Tonga's new constitution, voters directly elected 17 seats in parliament, while nine spots were reserved for nobles, including Tu'ivakano.
Previously, the tiny Pacific kingdom was run by a parliament dominated by a clique of nobles selected by the king, who also chose the prime minister and cabinet.
The swing towards democracy followed riots in the capital Nuku'alofa in 2006, which claimed eight lives and destroyed much of the business centre as people protested against the slow pace of political reform.
From : BBC News