Who is in control in north-eastern Syria?
Until Turkey launched its offensivethere on 9 October, the region was controlled by the Syrian Democratic Forces (SDF), which comprises militia groups representing a range of ethnicities, though its backbone is Kurdish.
Since the Turkish incursion, the SDF has lost much of its territory and appears to be losing its grip on key cities. On 13 October, Kurdish leaders agreed to allow Syrian regime forces to enter some cities to protect them from being captured byTurkeyand its allies. The deal effectively hands over control of huge swathes of the region to Damascus.
That leaves north-easternSyriadivided between Syrian regime forces, Syrian opposition militia and their Turkish allies, and areas still held by the SDF for now.
On 17 October Turkish president,Recep Tayyip Erdoan, agreed with US vice-president Mike Pence, to suspend Ankaras operation for five days in order to allow Kurdish troops to withdraw. The following week, on 22 October, Erdoan and his Russian counterpart, Vladimir Putin agreed on the parameters of the proposed Turkish safe zone in Syria.
How did the SDF come to control the region?
Before the SDF was formed in 2015, the Kurds had created their own militias who mobilised during the Syrian civil war to defend Kurdish cities and villages and carve out what they hoped would eventually at least become a semi-autonomous province.
In late 2014, theKurds were strugglingto fend off an Islamic State siege of Kobane, a major city under their control. With US support, including arms and airstrikes, the Kurds managed to beat back Isis and went on to win a string of victories against the radical militant group. Along the way the fighters absorbed non-Kurdish groups, changed their name to the SDF and grew to include 60,000 soldiers.
Why does Turkey oppose the Kurds?
For years, Turkey has watched the growing ties between the US and SDF with alarm. Significant numbers of the Kurds in the SDF were also members of the Peoples Protection Units (YPG), an offshoot of the Kurdistan Workers party (PKK) that has fought an insurgency against the Turkish state for more than 35 years in which as many as 40,000 people have died. The PKK initially called for independence and now demands greater autonomy for Kurds insideTurkey.
Turkey claims the PKK has continued to wage war on the Turkish state, even as it has assisted in the fight against Isis. The PKK is listed as a terrorist group by Turkey, the US, the UK, Nato and others and this has proved awkward for the US and its allies, who have chosen to downplay the SDFs links to the PKK, preferring to focus on their shared objective of defeating Isis.
What are Turkeys objectives on its southern border?
Turkey aims firstly to push the SDF away from its border, creating a 20-mile (32km) buffer zone that would have been jointly patrolled by Turkish and US troops until Trumpsrecent announcementthat American soldiers would withdraw from the region.
Erdoan has also said he would seek to relocate more than 1 million Syrian refugees in this safe zone, both removing them from his country (where their presence has started to create a backlash) and complicating the demographic mix in what he fears could become an autonomous Kurdish state on his border.
How would a Turkish incursion impact on Isis?
Nearly 11,000 Isis fighters, including almost 2,000 foreigners, and tens of thousands of their wives and children, are being held in detention camps and hastily fortified prisons across north-eastern Syria.
SDF leaders have warned they cannot guarantee the security of these prisoners if they are forced to redeploy their forces to the frontlines of a war against Turkey. They also fear Isis could use the chaos of war to mount attacks to free their fighters or reclaim territory.
On 11 October, it was reported that at least five detained Isis fighters had escaped a prison in the region. Two days later, 750 foreign women affiliated to Isis and their children managed to break out of a secure annex in the Ain Issa camp for displaced people, according to SDF officials.
It is unclear which detention sites the SDF still controls and the status of the prisoners inside.