What just happened in Syria and who is responsible?

The Assad family ruled Syria for more than 50 years with an iron fist. And now that has come to an end.

Bashar al-Assad became president after the death of his father, Hafez, in 2000, who ruled the country for nearly three decades.

In 2011, he brutally crushed a peaceful pro-democracy uprising, sparking a devastating civil war in which more than half a million people were killed and another 12 million forced to flee their homes.

Thirteen days ago, the armed Islamic group Hay'at Tahrir al-Sham and allied rebel factions launched a major offensive in northwestern Syria.

The rebels quickly captured the country's second-largest city, Aleppo, and then swept south on the highway to the capital, Damascus, as the army collapsed.

Russia announced that Assad had stepped down and left Syria on Sunday, hours after opposition fighters entered Damascus and crowds gathered in the streets to celebrate. It later emerged that Assad had flown to Moscow and was granted asylum.

Meanwhile, the leader of Hay'at Tahrir al-Sham, Abu Muhammad al-Julani, arrived in Damascus and told the Syrians: “The future is ours.”

For the past four years, there has been a feeling that the civil war has effectively ended.

Assad's government has regained control of most Syrian cities with the help of Russia, Iran, and Iranian-backed militias such as Hezbollah, and the front lines have been largely frozen.

However, large parts of the country remained outside government control.

The last stronghold of the rebels was in Aleppo and Idlib provinces, on the border with Türkiye, where more than four million people live, many of them displaced. It was dominated by Hay'at Tahrir al-Sham, but a number of rebel groups and allied jihadist groups were also based there. The Turkish-backed opposition factions also took control of the lands with the support of Turkish forces.

On November 27, Hay'at Tahrir al-Sham and its allies launched their surprise attack.

Three days later, they took control of most of Aleppo – the second largest city in Syria. They said they faced little resistance on the ground after the government quickly withdrew its troops and security forces.

Meanwhile, Turkish-backed opposition factions took advantage of the government's retreat by launching a separate attack on territory north of Aleppo controlled by the US-backed Kurdish-led militia alliance, the Syrian Democratic Forces.

Assad vowed to “crush” the rebels with the help of his allies. Russian warplanes have intensified their strikes on rebel-controlled areas and Iranian-backed militias have sent reinforcements to assist the army near Hama – the next city south on the way to Damascus.

But Hama fell to the rebels on Thursday, after several days of fierce battles that eventually prompted the army to withdraw.

The rebels declared their next goal was to capture Homs, Syria's third-largest city, and they achieved that on Saturday night after just one day of fighting. At the same time, other rebel factions reached the outskirts of Damascus.

Early on Sunday, opposition fighters led by Hay'at Tahrir al-Sham announced that they had entered Damascus and released detainees there. The country's most famous military prison, Saydnaya.

Less than two hours later, they announced: “The tyrant Bashar al-Assad has fled.”

The rebels also promised to build “a homeland for all sects and social classes.”

The Syrian Observatory for Human Rights, a UK-based monitoring group, reported that at least 910 people had been killed, including 138 civilians, since the rebel offensive began.

The armed Islamic group that led the offensive against Assad was founded in 2012 under a different name, Jabhat al-Nusra.

The Nusra Front, which pledged allegiance to Al Qaeda the following year, was considered one of the most effective and lethal groups fighting President Assad.

But it was feared for its jihadist ideology, and was seen as at odds with the main largely secular rebel coalition – the Free Syrian Army.

In 2016, Jabhat al-Nusra severed its ties with al-Qaeda and took the name Hay'at Tahrir al-Sham when it merged with other factions a year later.

However, the United Nations, the United States, the United Kingdom and a number of other countries still consider Hay'at Tahrir al-Sham to be affiliated with al-Qaeda and often refer to it as the Al-Nusra Front. The United States designated Abu Muhammad al-Julani as a global terrorist and offered a $10 million reward for information leading to his arrest.

Hay'at Tahrir al-Sham strengthened its power in Idlib and Aleppo provinces by crushing its rivals, including Al-Qaeda and Islamic State cells. It formed the so-called Syrian Salvation Government to administer the region in accordance with Islamic law.

For several years, Idlib remained a battleground as Syrian government forces tried to regain control.

But in 2020, Türkiye and Russia brokered a ceasefire To stop the government's campaign to regain control of Idlib. The ceasefire has largely held despite intermittent fighting.

Hay'at Tahrir al-Sham and its allies said so on November 27 They launched an attack to “deter aggression”The government and allied militias backed by Iran were accused of escalating attacks on civilians.

But it came at a time when the government had been weakened by years of war, sanctions and corruption, with its allies Russia and Iran preoccupied with other conflicts.

The Iranian-backed Hezbollah group recently suffered from the Israeli attack on Lebanon. Israeli strikes had eliminated Iranian military commanders in Syria, and Russia was distracted by the war in Ukraine.

Without them, Assad's forces were left exposed.

Outgoing Prime Minister Mohamed Jalili said on Monday that most members of his previous government were working with the rebels “so that the transitional period will be quick and smooth.”

The rebels said in a brief statement that their forces were close to taking full control of Damascus and preserving public property. They also said that the new Syrian government would begin its work as soon as it was formed.

The National Coalition for Syrian Revolutionary and Opposition Forces, which represents former opposition factions, said on Sunday that it is committed “to completing the transfer of power to a transitional governing body with full executive powers, paving the way for free democracy and freedom.” And a pluralistic Syria.”

The statement did not mention Hay'at Tahrir al-Sham, but its vice president, Dima Moussa, told the BBC that “the transitional phase requires the unification of all the Syrian people, including those who carry weapons.”

Meanwhile, the war continues in other parts of Syria.

Hay'at Tahrir al-Sham and its allies said that their forces were advancing in the western countryside of Deir ez-Zor, the largest city in eastern Syria.

Turkey-backed rebel factions fighting under the banner of the Syrian National Army are also advancing northwest of Aleppo into territory controlled by the Kurdish-led Syrian Democratic Forces.

Israel confirmed that it was attacking suspected government chemical weapons and missile sites in Syria, saying this was aimed at preventing them from falling into the hands of extremists. It also said it would maintain a “limited” troop presence in the demilitarized buffer zone in part of the Golan Heights because Syrian forces had abandoned their positions there.

Former Assad loyalists appear to still control the Mediterranean coast and mountains in the west of the country. The area is a stronghold of Assad's Alawite minority and also the location of two major Russian military bases – the Hmeimim air base and the naval base in Tartus.

Russian media said that Bashar al-Assad and his family had been granted asylum. Kremlin spokesman Dmitry Peskov said that Russia was “surprised” like everyone else by what happened and that Syria was “going through a very difficult period now due to instability.”

Iran expressed its hope for “a rapid end to military conflicts, the prevention of terrorist acts, and the start of a national dialogue” with all segments of Syrian society.

Türkiye said that Syria has now reached a stage in which “the Syrian people will shape the future of their country.” Foreign Minister Hakan Fidan said the new government “must be formed in an organized way” and warned that “the principle of inclusion must never be compromised.”

US President Joe Biden said the collapse of Assad's government was an “essential act of justice” after decades of repression, but warned that the Islamist rebels' takeover had created a moment of “danger and uncertainty.”

Israeli Prime Minister Benjamin Netanyahu said the collapse of Assad's government was a “direct result” of his country's action against Hezbollah and Iran.

Iraq, where powerful Iranian-backed militias have sent fighters to support the Syrian army in the civil war, said it supports efforts to open a dialogue in Syria that “leads to the adoption of a pluralistic constitution that preserves the human and civil rights of Syrians.”

Jordanian King Abdullah, whose country supported opposition factions at the beginning of the war, said that Jordan respects the will and choices of the Syrian people. He stressed the importance of avoiding “any conflict that might lead to chaos.”

European Union foreign policy chief Kaja Kallas described Assad's fall as a “positive and long-awaited development” and said the EU's priority was to ensure security in the region.