FACTBOX-Tension over Kurds on Turkey-Iraq border

(Reuters) - The Turkish army carried out an "intense intervention" against Kurdish rebels in northern Iraq on Saturday, sending in special forces a day after the cabinet authorised a cross-border operation.

Following are some of the details behind the tension:

* KURDISH HISTORY:

-- The Kurds are a non-Arab, mainly Sunni Muslim people, speaking a language related to Persian and living in a mountainous area straddling the borders of Armenia, Iraq, Iran, Syria and Turkey.

-- For most of their history they have been subjugated. In modern times Iran, Iraq and Turkey have resisted an independent Kurdish state and the Western powers have seen no reason to help establish one.

-- Kurdish nationalism stirred in the 1890s when the Ottoman Empire was on its last legs. The 1920 Treaty of Sevres, which imposed a settlement and colonial carve-up of Turkey after World War One, promised them independence.

-- Three years later, Turkish leader Kemal Ataturk tore up the treaty. Kurdish revolts in the 1920s and 1930s were put down by Turkish forces. The Kurds were not recognised as a separate people or allowed to speak their language in public.

* FIGHT FOR A HOMELAND:

-- The Kurdistan Workers Party (PKK), named in 1978, took up arms against Turkey in 1984 with the aim of creating an ethnic homeland in the southeast. Since then nearly 40,000 people have been killed in the conflict.