A chronology of key events:
15th century - Islamic sultanate of Brunei nominally in control of Borneo, including Sabah and Sarawak states of Malaysia, and some parts of the Sulu islands in the Philippines.
1521 - Brunei visited by Spanish navigator Juan Sebastian del Cano.
1841 - Sultan of Brunei Omar Ali Saifuddin II rewards British army officer James Brooke for helping to quell a civil war by granting him control of Sarawak.
1846 - Brunei reduced to its present size after ceding the island of Labuan to Britain.
1849-54 - British destroy Malay pirates operating between Singapore and Borneo.
1888 - Brunei becomes a British protectorate.
1906 - Brunei administered by a British resident, with the sultan having nominal authority.
1929 - Oil extraction begins.
1941-45 - Japan occupies Brunei.
1950 - Omar Ali Saifuddin III inaugurated sultan.
1959 - Sultan Omar introduces Brunei's first written constitution which enshrines Islam as the state religion and keeps Britain in charge of defence and foreign affairs.
Rule by decree
1962 - Legislative Council election results annulled after leftist Brunei People's Party, which sought to remove the sultan from power, won all 10 elected seats in the 21-member council; sultan declares state of emergency and rules by decree.
1963 - Brunei decides to remain a British dependency rather than join the Federation of Malaysia.
1967 - Hassanal Bolkiah becomes sultan following the abdication of his father, Sultan Omar, who nonetheless remains chief adviser.
1984 - Brunei becomes independent.
1985 - Government legalises the Brunei National Democratic Party (BNDP).
1986 - Brunei National Solidarity Party (BNSP) becomes legal; former Sultan Omar dies.
1988 - BNDP and BNSP banned.
1990 - Sultan Bolkiah introduces ideology of Malay Muslim Monarchy.
1995 - Government allows BNSP to operate, but the party is targeted for harassment and becomes inactive.
1998 - Sultan Bolkiah removes his younger brother, Prince Jefri Bolkiah, as chief of Brunei Investment Agency over concerns about his stewardship of agency; Sultan Bolkiah's eldest son, Prince Al-Muhtadee Billah, becomes heir apparent.
2000 - Brunei files civil suit against Prince Jefri Bolkiah for alleged misuse of state funds. Case is settled out of court. Court documents reveal that he spent $2.7 billion on luxury goods over 10 years. Prince agrees to return all assets allegedly taken from state-owned investment agency.
2000 August - Brunei says it will retrain up to 25% of the workforce to diversify the economy away from oil and to develop alternative industries such as tourism.
2001 - Auction is held of more than 10,000 items belonging to Prince Jefri.
2001 November - As chair of Association of South East Asian Nations (Asean), Brunei hosts body's 2001 summit. Leaders pledge to cooperate in fighting terrorism but push back launch date for Asian free trade area.
2004 September - Sultan Hassanal Bolkiah reopens parliament, 20 years after it was disbanded. The new parliament has 21 appointed members. The sultan later amends the constitution to allow the direct election of 15 members of the next parliament, but no poll date is set.
2005 May - Major cabinet reshuffle ushers in younger faces and ministers with private sector experience.
2005 August - National Development Party registered as political party.
2007 February - Brunei, along with Indonesia and Malaysia, signs a "Rainforest Declaration", agreeing to conserve a large area of Borneo that is home to rare species.
2007 November - Former finance minister and Sultan's brother, Prince Jefri Bolkiah, loses appeal at Brunei's highest court and is ordered to return property, cash and luxury goods allegedly acquired through misappropriated state funds.
2007 December - Amnesty international criticises Brunei's corporal punishment laws. Reports say 68 foreigners were flogged in 2008 for immigration offences. Immigration rules were tightened in 2004 to prevent illegal stay of migrant workers.
2008 June - UK judge issues warrant for the arrest of Prince Jefri Bolkiah after he failed to attend a High Court hearing over allegations that he violated a court order to return billions of dollars in missing funds to the Brunei government.
2010 February - Brunei included in France's "blacklist" of tax havens. French businesses operating in Brunei face increased taxes at home.
2010 June - US adds Brunei to its human trafficking watch list as a destination for forced labour and prostitution.
2010 December - Malaysia and Brunei agree to jointly develop two oil areas off Borneo, ending a border dispute dating from 2003 which held up exploration.
2014 April - Brunei becomes the first east Asian country to adopt sharia law, despite widespread condemnation from international human rights groups.
2016 September - Brunei ratifies the Paris global climate agreement.