The so-called Islamic State (IS) is also known as ISIS, ISIL or Daesh.
The final towns and cities once held by the militant group were liberated last month, with confirmation coming from the US-backed Syrian Democratic Forces (SDF).
The UK's contribution to the fight against Daesh, Operation Shader, has been active for more than four years and will continue despite last month's significant milestone in the battle against the terror group.
The militants dislike being referred as 'Daesh' because it's similar to two Arabic words: 'Daes', which translates to 'one who crushes something underfoot', and 'Dahes', meaning 'one who sows discord'.
But now it is close to facing the defeat of its self-proclaimed caliphate.
Here is a timeline of how the events unfolded:
2004 - 2012
The group was formed from the remnants of al-Qaeda in Iraq, following the 2003 US-led invasion of the country by Abu Musab al Zarqawi.
In 2006, as al-Zarqawi dies in a US strike and Abu Ayyub al Masri replaces him.
He officially establishes the Islamic State in Iraq (ISI) and chooses Abu Bakr al-Baghdadi as the group leader.
For several years, they are fairly quiet and it is only as tensions in the Middle East start to grow that the group regains relevance.
In 2011, the group starts to reemerge and carry out attacks.
2013 - 2014
In 2013, the group officially breaks with al-Quaeda and is renamed by al-Baghdadi Islamic State in Iraq and the Levant (ISIL).
In June 2014, IS militants seize Falluja and Raqqa while also targeting Mosul and Tikrit.
Following said offensives and the capture of Mosul, they announce the formation of a caliphate from Syria to Iraq, and rename the group the Islamic State of Iraq and Syria (ISIS).
In Iraq and Syria, IS troops kill thousands of people belonging to the Sheitaat tribe and Yazidis in Sinjar.
Women and girls captured (a number estimated to be around 7,000) are forced into sexual slavery.
2014 is also the year the group carries out an attack in Belgium at the Brussels Jewish Museum.
Social media play a big role in sharing the crude images and footage of US journalist James Foley's beheading.
In September, the United States built a military coalition against the Islamic State and began air strikes against the cities captured by the Islamist group.
In January 2015, IS attackers target a French satirical paper, Charlie Hebdo, and carry out a strike against the newspaper and a kosher supermarket, which results in 12 deaths.
The attack to the Charlie Hebdo offices marks the beginning of a regular series of bloody attacks in Europe and North America and brutalities in Libya against Christians.
In June 2016, Fallujah is taken back by Iraq.
Two months later, the Kurdish YPG takes back Manbij in Syria.
Soon after the Kurdish YPG takes control of the Syrian city, Turkey launches an offensive into Syria against both IS and the YPG.
On 22 March 2017, six people die and 50 people are injured in a terror attack in Westminster, London, near the Houses of Parliament.
Two months later, on 22 May 2017, a suicide bomber targets people attending the concert of US singer Ariana Grande. This resulted in 22 deaths and 59 people injured.
On 3 June 2017, a van hits pedestrians near London Bridge before attackers abandoned the vehicle and stabbed people around Borough Market. The attack resulted in seven people dead and 48 injured.
While it is a dark year in the UK, is it also a dark year for IS in the Middle East as the group suffers several defeats.
Mosul is taken back by Iraq and Baghdad declares the end of the caliphate.
Russia and Iran back the Syrian army and IS loses control of Raqqa.
Despite the substantial losses suffered by IS in 2017, US government and foreign experts are warned that the group has still as many as 10,000 loyalists in both Iraq and Syria.
IS loses the enclaves in Yarmouk and on the frontier with the Golan Heights to the Syrian government and the rest of the border to Iraqi forces.
In May, a group of senior IS officials who had been hiding in Turkey and Syria are captured by Iraqi-US forces.
In December, US President Donald Trump says IS has been defeated and promises to withdraw US troops from Syria.
In January, Tornado aircraft completed their final missions over Iraq and Syria as part of Operation Shader.
Two months later, the US-backed SDF said they have liberated the last area held by IS in the eastern village of Baghouz in Syria.
Following the milestone, it was confirmed Operation Shader would continue, with Daesh not being completely defeated.
Around 400 American troops are to remain in Syria, 200 of which will be on a peacekeeping mission.
A concise timeline
- 2004 - IS emerges from a fraction of al-Qaeda in Iraq
- 2011 - Abu Bakr al-Baghdadi leads attacks in Iraq and Syria
- 2013 - Islamic State in Iraq and the Levant (ISIL) breaks from al-Qaeda
- May 2014 - IS carry out an attack at the Jewish Museum in Belgium
- Jun 2014 - IS seize Falluja, Raqqa and Mosul
- Sep 2014 - US military coalition and strikes against IS
- Jan 2015 - IS carry out an attack against French satirical paper Charlie Hebdo
- May 2015 - IS seize Palmyra
- Jun 2016 - Fallujah is taken back by Iraq.
- Aug 2016 - the Kurdish YPG takes back Manbij in Syria
- 2017 - attacks carried out in the UK (Manchester Arena bombing, Westminster attack, London Bridge attack)
- 2017 - IS suffers defeats and loses control of Mosul and Raqqa
- 2018 - IS continues to suffer losses and US say they will withdraw troops
- 2019 - US to leave 400 troops in Syria and say most territory has been regained
- 2019 - IS loses last terrirtory in Iraq and Syria, but the group's complete defeat is not confirmed