Once the centre of the Islamic Caliphate, Syria covers an area that has seen invasions and occupations over the ages, from Romans and Mongols to Crusaders and Turks.
A country of fertile plains, high mountains and deserts, it is home to diverse ethnic and religious groups, including Kurds, Armenians, Assyrians, Christians, Druze, Alawite Shia and Arab Sunnis, the last of who make up a majority of the Muslim population.
Modern Syria gained its independence from France in 1946, but has lived through periods of political instability driven by the conflicting interests of these various groups.
From 1958-61 it united with Nasser's Egypt, but an army coup restored independence before the pan-Arab nationalist Baath (Renaissance) party took control in 1963.
A mainly Alawite faction of military leaders soon established firm control, but an uprising in 2011 has since seen the country descend into civil war.
The Baath government saw authoritarian rule at home and a strong anti-Western policy abroad, particularly under President Hafez al-Assad from 1970 to 2000.
In 1967 Syria lost the Golan Heights to Israel after the Arab defeat in the Six Day War. Civil war in neighbouring Lebanon in the 1970s allowed it to extend its political and military influence in that country.
The Assad government dealt harshly with domestic opposition. Tens of thousands are estimated to have been killed in the suppression of the 1982 Muslim Brotherhood uprising in Hama.
In 2011-12, security forces tried to crush anti-government street protests inspired by the Arab Spring. These protests rapidly turned into civil war, with Islamist groups and regional powers gradually joining the fray.
The rise of the Al-Nusra front, a radical Islamist militia allied to al-Qaeda, in rebel ranks led to a marked cooling of international and regional support for the opposition in mid-2013
This allowed the government and its Iranian-backed Lebanese Hezbollah allies to launch a counter-offensive.
Large swathes of Syrian territory remain in rebel hands, and jihadists from the self-styled Islamic State have made significant gains on the ground in Syria as well as in neighbouring Iraq.
In 2015, Russia intervened in the conflict, saying it was seeking to combat Islamic State, but the opposition and the West accused it of hitting anti-Assad rebels hardest.
Turkey followed suit in 2016, sending in troops to help Turkish-backed rebels push back so-called Islamic State militants and Kurdish rebels, whom Ankara considers a threat.