A chronology of key events:
7th-10th cent AD - Hindu and Buddhist Dvaravati culture, thought to be of the ethnic Mon people, predominates.
10th-14th cent - Southern Thailand is ruled by the mainly Mon Lavo Kingdom, but with growing influence from the Khmer neighbouring Empire. (modern-day Cambodia). The Tai people - the antecedents of modern ethnic Thais - start to move southwards into the area.
1238-1448 - Thai-speaking Sukhothai kingdom expands its rule further south, coming to dominate much of modern-day Thailand, before being eclipsed by a rival Thai kingdom in the south, Ayutthaya.
1350-1767 - Ayutthaya kingdom gradually brings Thailand under its control and becomes a major power in Southeast Asia. At its greatest extent around 1600, it rules parts of modern-day Cambodia, Laos and Burma.
1448 - King Ramesuan joins Ayutthaya and Sukhothai in personal union.
1590-1605 - Reign of Naresuan. Seen as Ayutthaya's greatest king, he ends a period of Burmese overlordship and briefly conquers Cambodia and parts of southern Burma.
1767 - Invading Burmese forces sack the capital, Ayutthaya, bringing an end to the kingdom.
1768-1782 Under Taksin the Great, an ethnic Thai Chinese, the shortlived Thonburi Kingdom re-establishes Thai control. Taksin is toppled by a coup launched by General Chao Phraya Chakri, who founds a new dynasty centred on Bangkok.
Rise of modern Thailand
1782 - Beginning of the Chakri dynasty under King Rama I, which rules to this day. The country is known as Siam. New capital of Bangkok founded.
1851-1868 - Reign of King Mongkut (Rama IV), who embraces Western innovations and initiates Thailand's modernisation.
1868-1910 - Reign of King Chulalongkorn. Employment of Western advisers to modernise Siam's administration and commerce. Railway network developed.
1917 - Siam becomes ally of Great Britain in World War I.
1932 - Bloodless coup against absolute monarch King Prajadhipok. Constitutional monarchy introduced with parliamentary government.
1939 - Siam changes its name to Thailand ("Land of the Free").
1941 - Japanese forces land. After negotiations Thailand allows Japanese to advance towards British-controlled Malay Peninsula, Singapore and Burma.
1942 - Thailand declares war on Britain and US, but Thai ambassador in Washington refuses to deliver declaration to US government.
1945 - End of World War II. Thailand compelled to return territory it had seized from Laos, Cambodia and Malaya. Exiled King Ananda returns.
1946 - King Ananda dies in mysterious shooting incident.
1947 - Military coup by the wartime, pro-Japanese leader Phibun Songkhram. The military retain power until 1973.
1965 onwards - Thailand permits US to use bases there during the Vietnam War. Thai troops fight in South Vietnam.
Brief civilian rule
1973 - Student riots in Bangkok bring about the fall of the military government. Free elections are held but the resulting governments lack stability.
1976 - Military takes over again.
1978 - New constitution promulgated.
1991 - Military coup, the 17th since 1932. A civilian, Anand Panyarachun, is installed as prime minister.
1992 - Elections in September see Chuan Leekpai, leader of the Democratic Party, chosen as prime minister.
1995 - Government collapses. Banharn Silpa-archa, of the Thai Nation party, elected prime minister.
1996 - Banharn government resigns, accused of corruption. Chavalit Yongchaiyudh of the New Aspiration party wins elections.
1997 - Asian financial crisis: The baht currency falls sharply against the dollar, leading to bankruptcies and unemployment. The IMF steps in. Chuan Leekpai becomes prime minister.
1998 - Tens of thousands of migrant workers are sent back to their countries of origin. Prime Minister Chuan involves the opposition in his government in order to push through economic reforms.
2001 January - New Thai Love Thai party wins elections. Thaksin Shinawatra forms coalition government.
2004 January-March - Martial law is imposed in largely-Muslim south after more than 100 killed in a wave of attacks blamed on ethnic-Malay separatists.
2004 December - Thousands of people die when a massive tsunami, triggered by an undersea earthquake off the coast of Sumatra, devastates communities on the south-west coast, including the resort of Phuket.
2006 September-October - Military leaders stage a bloodless coup while Prime Minister Thaksin Shinawatra is at the UN General Assembly. Retired General Surayud Chulanont is appointed interim prime minister.
2007 August - Voters approve a new, military-drafted constitution in a referendum.
2008 February - Return to civilian rule after December elections. Samak Sundaravej of the Thaksin-linked People Power Party (PPP) is sworn in as prime minister. Ousted premier Thaksin Shinawatra returns from exile.
2008 August - Thaksin flees to Britain with his family after failing to appear in court to face corruption charges.
2010 March-May - Tens of thousands of Thaksin supporters - in trademark red shirts - paralyse parts of central Bangkok with months-long protests calling for early elections. Troops eventually storm the protesters' barricades, leaving 91 dead.
2011 July - The pro-Thaksin Pheu Thai party wins a landslide victory in elections. Yingluck Shinawatra - the sister of Mr Thaksin Shinawatra - becomes prime minister.
2013 February - Government and separatists in south sign first-ever peace talks deal.
2014 May - Constitutional court orders Prime Minister Yingluck Shinawatra and several ministers out of office over alleged irregularities in appointment of security adviser. Army seizes power in coup.
2016 August - Voters approve a new constitution giving the military continuing influence over the country's political life.
Death of King Bhumibol Adulyadej
2016 October - King Bhumibol Adulyadej, the world's longest reigning monarch, dies at the age of 88 after 70 years on the throne.
2016 - December - Crown Prince Vajiralongkorn is proclaimed king.
2017 April - King Vajiralongkorn signs the new, military-drafted constitution that paves the way for a return to democracy.
2019 March - General election sees former general Prayut Chan-o-cha returned to power as prime minister.
2019 November - Suspected separatists kill at least 15 people in southern Thailand, in one of the country's worst attacks in years.