Timeline of the rise and fall of the Islamic State group

The Islamic State group erupted from the chaos of Syria and Iraq's conflicts and swiftly did what no Islamic militant group had done before, conquering a giant stretch of territory and declaring itself a "caliphate."

Its territorial rule, which at its height in 2014 stretched across nearly a third of both Syria and Iraq, ended with a last stand by several hundred of its militants at a tiny Syrian village on the banks of the Euphrates near the border with Syria.

Here are the key moments in the rise and fall of the Islamic State group:

FILE - This image made from video posted on a militant website July 5, 2014, purports to show the leader of the Islamic State group, Abu Bakr al-Baghdadi, delivering a sermon at a mosque in Iraq during his first public appearance. President Donald Trump declared victory over the Islamic State group in Syria in a tweet Thursday, Dec. 20, 2018, but the militants remain a deadly force, and U.S. partners warn a premature U.S. withdrawal will allow them to storm back. The jihadists still hold territory in Syria and top leaders, including the group's self-styled caliph Abu Bakr al-Baghdadi, remain at large. (Militant video via AP, File)

April 2013 — Abu Bakr al-Baghdadi, the leader of al-Qaida's branch in Iraq, announces the merger of his group with al-Qaida's franchise in Syria, forming the Islamic State in Iraq and the Levant and expanding his reach into neighboring Syria.

2014

January — Al-Baghdadi's forces overrun the city of Fallujah in Iraq's western Anbar province and parts of the nearby provincial capital of Ramadi. In Syria, they seize sole control of the city of Raqqa after driving out rival Syrian rebel factions, and it becomes their de facto capital.

FILE - This undated photo released Tuesday, Aug. 25, 2015, file photo, on a social media site used by Islamic State militants, which has been verified and is consistent with other AP reporting, shows smoke from the detonation of the 2,000-year-old temple of Baalshamin in Syria's ancient caravan city of Palmyra. (Islamic State social media account via AP, File)

February — Al-Qaida leader Ayman al-Zawahri disavows al-Baghdadi after the Iraqi militant ignores his demands that IS leave Syria.

June — IS captures Mosul, Iraqi's second-largest city, and pushes south as Iraqi forces crumble, eventually capturing Saddam Hussein's hometown of Tikrit and reaching the outskirts of Baghdad. When they threaten Shiite holy sites, Iraq's top Shiite cleric issues a call to arms, and masses of volunteers, largely backed and armed by Iran, join militias.

June 29 — The group renames itself the Islamic State and declares the establishment of a self-styled "caliphate," a traditional model of Islamic rule, in its territories in Iraq and Syria. Al-Baghdadi is declared the caliph.

FILE - In this Sunday, March 30, 2014, file photo, Islamic State group militants hold up their flag as they patrol in a commandeered Iraqi military vehicle in Fallujah, 40 miles (65 kilometers) west of Baghdad, Iraq. (AP Photo, File)

July 4 — Al-Baghdadi makes his first public appearance, delivering a Friday sermon in Mosul's historic al-Nuri Mosque. He urges Muslims around the world to swear allegiance to the caliphate and obey him as its leader.

August — IS captures the town of Sinjar west of Mosul and begins a systematic slaughter of the tiny Yazidi religious community. Women and girls are kidnapped as sex slaves; hundreds remain missing to this day.

Aug. 8 — The U.S. launches its campaign of airstrikes against IS in Iraq.

FILE - This Wednesday, Dec. 24, 2014, this image posted by the Raqqa Media Center, which monitors events in territory controlled by Islamic State militants with the permission of the extremist group, shows militants with a captured pilot, center right, wearing a white shirt in Raqqa, Syria. (AP PhotoRaqqa Media Center, File)

Sept. 22 - The U.S.-led coalition begins an aerial campaign against IS in Syria.

2015

January — Iraqi Kurdish fighters, backed by U.S.-led airstrikes, drive IS out of several towns north of Mosul. In Syria, Kurdish fighters backed by U.S. airstrikes repel an IS onslaught on the town of Kobani on the border with Turkey, the first significant defeat for IS.

FILE - This file image made from undated video posted during the weekend of June 28, 2014, on a social media account frequently used for communications by the Islamic State of Iraq and the Levant (ISIL), which has been verified and is consistent with other AP reporting, shows Omar al-Shishani standing next to the group's spokesman among a group of fighters as they declare the elimination of the border between Iraq and Syria. (AP Photomilitant social media account via AP video, File)

April 1 — U.S.-backed Iraqi forces retake Tikrit, their first major victory against IS.

May 20 — IS captures the ancient Syrian town of Palmyra, where the extremists later destroy archaeological treasures.

2016

FILE - In this July 27, 2017, file photo, U.S.-backed Syrian Democratic Forces fighters prepare to fire a mortar shell against the Islamic State militants, at one of the front lines, in Raqqa, northeast Syria. (AP PhotoHussein Malla, File)

Feb. 9 — Iraqi forces recapture Ramadi after months of fighting and at enormous cost, with thousands of buildings destroyed. Almost the entire population fled the city.

June 26 — Fallujah is declared liberated by Iraqi forces after a five-week battle.

July 3 — IS sets off a gigantic suicide truck bomb outside a Baghdad shopping mall, killing almost 300 people, the deadliest attack in Iraq since the 2003 U.S.-led invasion.

In this file photo released on Jan. 14, 2015, by a militant website, which has been verified and is consistent with other AP reporting, Islamic State militants kill a man they accused of being a homosexual by throwing him off a building in Syria's northeastern province of Hassakeh. (Militant website via AP, File)

Oct. 17 — Iraqi Prime Minister Haider al-Abadi announces the start of the operation to liberate Mosul.

Oct. 21 — IS militants and sleeper cells stage a wave of attacks with suicide blasts in the central Iraqi city of Kirkuk, killing at least 80 people in an attempt to divert attention from Mosul.

Nov. 5 — The U.S.-backed, Kurdish-led Syrian Democratic Forces launch Operation Euphrates Wrath, the first of five operations aiming to retake Raqqa, starting with an encircling of the city.

FILE - In this July 26, 2017, file photo, Syrians look at a U.S. armored vehicle convoy on a road that leads to Raqqa, northeast Syria. (AP PhotoHussein Malla, File)

2017

Jan. 24 — Al-Abadi announces eastern Mosul has been "fully liberated."

Feb. 19 — Iraqi forces begin the assault on western Mosul, taking the city's airport and nearby military base within four days.

FILE - In this October 28, 2014, file photo, smoke and flames rise from an Islamic State fighters' position in the town of Kobani during airstrikes by the US-led coalition seen from the outskirts of Suruc, near the Turkey-Syria border. (AP PhotoVadim Ghirda, File)

May 10 — SDF captures the strategic Tabqa dam after weeks of battles and a major airlift operation that brought SDF fighters and their U.S. advisers to the area. The fall of the dam facilitated the push on Raqqa, about 40 kilometers (25 miles) away.

June 6 — SDF fighters begin an attack on Raqqa from three sides, backed by U.S.-led coalition airstrikes.

June 18 — Iraqi forces launch battle for Mosul's Old City, the last IS stronghold there.

FILE - This a file frame grab from video posted online Friday, Jan. 18, 2019, by supporters of the Islamic State group, purports to show an IS fighter firing a weapon during clashes with members of the U.S.-backed Syrian Democratic Forces, in the eastern Syrian province of Deir el-Zour, Syria. (Militant Photo via AP, File)

June 21 — IS destroys Mosul's iconic al-Nuri Mosque and its 12th century leaning minaret as Iraqi forces close in, according to Iraqi and coalition officials.

July 10 — Iraqi prime minister declares victory over IS in Mosul and end of the extremists' caliphate in Iraq.

Oct. 17 — SDF takes full control of Raqqa after months of heavy bombardment that devastates the city.

FILE - In this June 27, 2016, file photo, a member of Iraqi counterterrorism forces stands guard near Islamic State group militant graffiti in Fallujah, Iraq. (AP PhotoHadi Mizban, File)

September-December —Syrian government forces, backed by Russian air power and Iranian forces, recapture IS territory on the western bank of the Euphrates River, seizing the cities of Deir el-Zour, Mayadin and Boukamal on the border with Iraq.

2018

Aug. 23 — IS leader al-Baghdadi resurfaces in his first purported audio recording in almost a year; he urges followers to "persevere" and continue fighting.

FILE - In this Thursday, Oct. 19, 2017 file photo, a frame grab made from drone video shows damaged buildings in Raqqa, Syria.(AP PhotoGabriel Chaim, File)

Sept. 10 — SDF launches a ground offensive, backed by U.S.-led coalition airstrikes, to take the last territory held by IS in Syria's eastern province of Deir el-Zour.

2019

February-March — SDF besiege IS in the village of Baghouz, the last scrap of land the group holds. The advance stalls as some 30,000 civilians, mostly families of IS members, are evacuated from the pocket over the course of weeks.

FILE - In this June 23, 2014, file photo, fighters from the Islamic State group parade in a commandeered Iraqi security forces armored vehicle in the northern city of Mosul, Iraq. (AP Photo, File)

March 23 — SDF declares the complete capture of Baghouz and the end of the Islamic State group's territorial "caliphate."

FILE - In this March 30, 2018, file photo, Alexanda Amon Kotey, left, and El Shafee Elsheikh, who were allegedly among four British jihadis who made up a brutal Islamic State cell dubbed "The Beatles," sit on a sofa during an interview with The Associated Press at a security center in Kobani, Syria. (AP PhotoHussein Malla, File)

FILE -In this Tuesday, July 18, 2017, file photo, suspected Islamic State members sit inside a small room in a prison south of Mosul. (AP PhotoBram Janssen, File)

FILE - This undated file photo posted Wednesday, Aug. 27, 2014, by the Raqqa Media Center of the Islamic State group, a Syrian opposition group, which has been verified and is consistent with other AP reporting, shows a fighter from the Islamic State group, armed with a knife and an automatic weapon, next to captured Syrian army soldiers and officers, following the battle for the Tabqa air base in Raqqa, Syria. (AP PhotoRaqqa Media Center of the Islamic State group, File)

FILE - In this July 3, 2017, file photo, smoke billows over the Old City after several strikes as Iraqi forces continue their advance against Islamic State militants in Mosul, Iraq, Monday, July 3, 2017. (AP PhotoFelipe Dana, File)

FILE - In this Oct. 17, 2016 file photo, a Kurdish Peshmerga convoy drives towards a frontline in Khazer, about 30 kilometers (19 miles) east of Mosul, Iraq. (AP PhotoBram Janssen, File)

FILE - In this June 29, 2016, file photo, Iraqi security forces inspect vehicles belonging to escaping Islamic State militants outside Fallujah, Iraq. (AP Photo, file)

In this file photo released on May 14, 2015, by a militant website, which has been verified and is consistent with other AP reporting, a member of the Islamic State group's vice police known as Hisba, right, reads out to Syrian citizens, background, a verdict handed down by an Islamic court sentencing many they accused of adultery to lashing, in Raqqa city, Syria. (Militant website via AP, File)