FACTBOX: Turkey launches land offensive into N.Iraq

(Reuters) - Turkey's military said on Friday it had launched a cross-border land offensive backed by fighter jets into northern Iraq on Thursday to hunt down Kurdish PKK guerrillas.

Turkey has said it has the right under international law to hit Kurdish PKK guerrillas who take shelter in northern Iraq and have mounted attacks inside Turkey that have killed scores of troops.

Iraq has repeatedly called for a diplomatic solution to deal with the PKK but Turkey's government is under domestic pressure to take military action against the rebels.

Following are some of the details behind the tensions:

* 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 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 recognized as a separate people or allowed to speak their language in public.