A chronology of key events
1907 - Ugyen Wangchuk is chosen as hereditary ruler
1910 - Treaty signed with British giving them control over Bhutan's foreign relations
1949 - Treaty signed with newly-independent India guaranteeing non-interference in Bhutan's internal affairs, but allowing Delhi influence over foreign relations
1952 - Reformist monarch Jigme Dorji Wangchuk succeeds to throne
1952 - National assembly established
1958 - Slavery abolished.
1959 - Several thousand refugees given asylum after Chinese annex Tibet
1964, 1965 - Prime minister killed in dispute among competing political factions. Unsuccessful attempt to assassinate monarch.
1968 - First cabinet established
1971 - Bhutan joins the UN
1972 - King Jigme Dorji Wangchuk dies and is succeeded by his son, Jigme Singye Wangchuk, who continues policy of cautious modernisation
1989 - Nepali ceases to be a language of instruction in schools.
1990 - Violent ethnic unrest and anti-government protests in southern Bhutan pressing for greater democracy and respect for Nepali rights. Bhutan People's Party begins campaign of violence. Thousands of ethnic Nepalis flee to Nepal.
1992 - Leader of illegal Bhutan People's Party sentenced to life imprisonment.
1993 - Bhutan and Nepal try to resolve refugee problem.
1998 - King cedes some powers to national assembly, giving up role as head of government; cabinet now elected by assembly; famous "Tiger's Lair" Buddhist monastery damaged by fire.
1999 - Limited television and internet services allowed; several dozen political prisoners released.
August 2001 - Bhutanese, Nepalese ministers meet to discuss the repatriation of Bhutanese refugees living in Nepal. Some 100,000 ethnic Nepalese say they were forced out of Bhutan in the 1980s and 1990s, alleging ethnic and political repression.
January 2002 - Indian state of Assam says two rebel groups still have camps in Bhutan, despite Bhutan's deadline for them to leave the country by the end of 2001.
December 2003 - Bhutanese soldiers fight Indian separatist rebels in an attempt to drive them from their bases in the south of the country.
March 2005 - Proposed constitution is unveiled. It envisages a parliamentary democracy and will be adopted or rejected in a referendum.
December 2005 - King Jigme Singye Wangchuck says he will abdicate in 2008, when democratic parliamentary elections are held. The crown prince will take over as monarch.