ANKARA: Despite their longstanding wish for a single homeland called Kurdistan, the Kurds are today scattered over four countries spanning half a million square kilometres: Iran, Iraq, Syria and Turkey.
Originally of Indo-European origin, the Kurds trace their roots back to the Medes of ancient Persia. Mainly Sunni Muslim, they live in mountainous regions straddling the four countries, and have kept their language, culture and tribal system.
While their population differs according to official or Kurdish sources, they number between 25 and 35 million.
The largest number of Kurds lives in Turkey, where their numbers are disputed, but believed to be between 12 and 15 million.
There are five million Kurds in Iran, about 4.5 million in Iraq and around two million in Syria.
Large expatriate Kurdish communities also exist in the former Soviet Union, notably Azerbaijan and Armenia, and in Lebanon and some European countries such as Germany.
As a large and distinct group Kurds are neither Arabs, Turks or Persians and are therefore seen as a political threat by all four of the countries that they inhabit.
In past centuries the Kurds enjoyed periods of self-rule under Kurdish dynasties in semi-autonomous principalities, some of which survived until the mid-19th century when they were overthrown by the Ottoman empire and Persia, as Iran was formerly called.
The Kurds' claim for an ethnic homeland, which dates back to 1695, has been the source of their problems in a history that has been a long tale of harassment, discrimination and occasionally of slaughter.
The traditional refuge of the Kurds has always been the mountains, with their steep pastures and fertile valleys.
Following the Turkish defeat in World War I and the collapse of the Ottoman empire, Kurdish demands for an independent homeland were recognised under the Treaty of Sevres (1920), but promises received from London and Paris were never implemented.
The Sevres treaty was re-negotiated at Lausanne in 1923 and the Kurdish demands were buried.
With Soviet backing, Iran's Kurds briefly declared a republic at the end of World War II, but it was soon crushed by the Iranian army.
In recent decades, Turkey and Iraq have been equally ruthless in frustrating Kurdish demands. Ankara banned until 2002 the use of the Kurdish language, and even the words Kurd and Kurdish were banished from public discourse.
Iraq under the regime of Saddam Hussein carried out a murderous campaign, systematically wiping out towns and villages using guns, planes and bulldozers.
In April 1988, near the end of the Iran-Iraq war, Iraqi warplanes attacked the Kurdish village of Halabja with poison gas, killing the entire population.
The US-led invasion of Iraq 10 years ago, and the subsequent fall of the Saddam regime gave Iraqi Kurds new hopes and they now enjoy wide-ranging autonomy on most issues, have their own parliament and government.
In Turkey, the Kurdistan Workers' Party (PKK) led by Abdullah Ocalan, who is expected to call for a ceasefire on Thursday, was formed in 1978 and in 1984 launched a campaign for a separate state, plunging southeast Turkey into a civil war in which some 45,000 people, mostly Kurds, have died.
In Iran, the western province of Kordestan is dominated by Sunni Muslims and has seen deadly fighting in recent years between Iranian security forces and Kurdish rebels of the PJAK group operating out of rear-bases in neighbouring Iraq.
PJAK (Party of Free Life of Kurdistan) is closely allied with Turkey's PKK.