Iraqi Troops close in on Ramadi
Iraqi troops have closed in on one of the last remaining districts in the city of Ramadi that is under ISIS control.
Recapturing Ramadi, which fell to the militants in May, would be one of the most important military operations by Iraq's armed forces since ISIS swept across a third of the country in 2014.
Military officials said the operation would last several days.
ISIS : ISIS in Iraq
ISIS was originally the Al Qaeda in Iraq (AQI) which later became the Islamic State in Iraq (ISI), which finally became the Islamic State in Iraq and Syria.
In January 2014, ISIS pushed back Iraqi troops and took control of parts of Fallujah and Ramadi two major cities close to the capital Baghdad.
By June 2014, Mosul, Iraq's second largest city fell to ISIS.
Jun 2014: A Caliphate and mass desertions weaken Iraqi army
By mid-2014, almost a third of Iraq, including Fallujah, Mosul, parts of Ramadi and Tikrit were under ISIS control.
In June 2014, ISIS declared itself as a Caliphate.
It also took over the Baiji Oil fields, a significant source of revenue.
This escalation prompted mass desertions by Iraqi army officers, who either wanted to join ISIS or escape the fighting in the country.
Aug 2014: US orders air-strikes, Kurds rally against ISIS
By August 2014, the US ordered airstrikes on ISIS positions in Iraq, to help the Iraqi army regain territory.
The mass executions of the Yazidi people prompted Kurdish Peshmerga forces to rally against ISIS.
By September 2014, the US announced a ten nation coalition to fight against ISIS.
However, ISIS continued to make gains and consolidated its control over the Anbar province by November.
May 2015: Coalition forces, Iraqi troops make gains
In January 2015, Kurdish forces took control of the city of Kobani after fighting ISIS for months.
Egypt and Jordan began conducting airstrikes on ISIS targets.
By April 2015, Iraqi troops, bolstered by air support provided by the coalition forces began an offensive to recapture lost territory and won back Tikrit.
Coalition countries including the US claimed that ISIS was now on the defensive.
May 2015: The fall of Ramadi
In May 2015, amidst heavy fighting, ISIS seized control of Ramadi.
Reports suggested that ISIS used seasonal sandstorms to their advantage as coalition forces could not conduct air-strikes during a sandstorm.
The lack of air support compelled Iraqi forces to flee Ramadi leaving large swathes of the city unguarded allowing ISIS to take over with relative ease.
Fact: A strategically located Sunni town
Ramadi is the capital of Iraq's Sunni majority Anbar province and occupies a highly strategic location next to the Euphrates river, on the road west that connects Iraq to Syria and Jordan.
24 May 2015: US criticises Iraq army for fall of Ramadi
The US Defence Secretary criticized the Iraqi army for their defeat in Ramadi.
The US stated that the Iraqi forces displayed a lack of will to fight ISIS and regain control of their country.
Iraqi officials condemned the US statements and blamed the defeat on the lack of coalition support.
However, they conceded that poor battlefield leadership by Iraqi commanders contributed to the defeat.
26 May 2015: Iraq launches Anbar offensive
On 26 May, the Iraqi government launched an offensive with the intent to clear the Anbar province of ISIS fighters.
By September 2015, no significant headway was made against the ISIS and the US announced a $24 million support package to further arm and train Iraqi forces and tribals against ISIS.
By November, Iraqi forces regained control of several key positions surrounding Ramadi.
28 Dec 2015: Iraqi Troops close in on Ramadi
30 Dec 2015: Leaders killed, Ramadi falls, ISIS losing Iraq
U.S. coalition forces killed 10 Islamic State leaders in air strikes, dealing a double blow to the militant group after Iraqi forces ousted it from the city of Ramadi.
The victory in Ramadi was officially declared after Iraqi Prime Minister Haider-al-Abadi planted the Iraqi flag after the army won back the city from ISIS's occupation.
The victory symbolizes ISIS's waning territorial influence in Iraq.