Here is a timeline:

- Creation -

In an April 2013 recording, the head of the Al-Qaeda-linked Islamic State of Iraq, Abu Bakr al-Baghdadi, announces the creation of a group called the Islamic State of Iraq and the Levant (ISIL).

Al-Qaeda disavows links with the new outfit by early 2014.

- Jihadist sweep -

ISIL fighters, backed by former officers of late dictator Saddam Hussein, capture Fallujah and parts of Ramadi, west of Baghdad, in January 2014.

Fallujah is the first major town to fall to the militants since the US-led invasion of 2003 that toppled Saddam.

In June, ISIL launches an offensive in northwestern Iraq, seizing Mosul and Sunni Arab areas bordering the autonomous Kurdistan region and routing the badly prepared Iraqi army without a fight.

- 'Caliphate' proclaimed -

Also in June, the group declares the creation of a "caliphate" in territories it holds in Iraq and Syria, rebranding itself the Islamic State (IS) and declaring Baghdadi the "caliph".

In early August, IS seizes several northwestern towns held by ethnic Kurds, including Sinjar. Tens of thousands of civilians flee into the mountains.

Thousands of women and young girls, in particular from the Yazidi minority, are subjected to rape, abduction and enslavement in IS-controlled zones, according to the United Nations.

- US-led coalition -

In August, US warplanes strike IS positions in northern Iraq and then form a coalition of more than 70 countries to fight the group in Iraq and Syria. Washington deploys 5,000 soldiers.

In March 2015, Iraq announces the "liberation" of Saddam's hometown of Tikrit, north of Baghdad, after nearly 10 months under IS rule.

In November, coalition-backed Kurdish forces retake Sinjar.

In February 2016, Anbar provincial capital Ramadi is recaptured and in June, Iraqi forces retake Fallujah.

A week later, an IS attack in Baghdad kills 320 people.

- Mosul recaptured -

On July 10, 2017, then Iraqi Prime Minister Haider al-Abadi declares victory in Mosul after a nearly nine-month offensive led by a 30,000-strong federal force backed by coalition air strikes.

In August, the last major IS urban stronghold in northern Iraq, Tal Afar, is declared "liberated". It is followed in October by Hawija, one of the few remaining IS holdouts.

- Victory proclaimed -

On December 9, Abadi declares victory in the three-year war against the IS, saying Iraqi forces are in "complete control" of the entire Iraqi-Syrian border.

The following day is declared a public holiday to celebrate, with a military parade through the capital.

The jihadists, however, maintain sleeper cells, including along the border with Syria, and have carried out periodic hit-and-run attacks.