The leaderless demonstrations, against a political system deemed as corrupt, then fizzled out.

They were then overshadowed by tensions between the United States and Iran, which almost degenerated into open conflict in Iraq.

A timeline:

- Protests erupt -

On October 1, 2019, more than a thousand people respond to calls on social media in Baghdad and cities in the largely Shiite south to protest against corruption, unemployment and poor public services.

Riot police use water cannon, teargas, rubber bullets and then live fire to disperse demonstrators.

As protests continue into October 2, the authorities close down Baghdad's high-security Green Zone, site of top state institutions and the US embassy.

On October 3, thousands defy a curfew in several cities, but are pushed back by tanks. The internet is cut across much of the country.

Influential Shiite cleric Moqtada Sadr calls on the government to resign.

Two days later, the cabinet announces land distribution, social welfare and anti-corruption reforms.

- Deadly second wave -

Protests resume on October 24, a day before the one-year anniversary of Adel Abdel Mahdi becoming prime minister.

At least 63 people are killed over two days, mainly in the south.

On October 28, students, professors and schoolchildren rally in Baghdad and southern cities.

Iran's supreme leader Ayatollah Ali Khamenei tells Iraq to "remedy insecurity", and on November 1, top cleric Grand Ayatollah Ali al-Sistani warns against foreign interference.

On November 9, after talks involving the commander of Iran's Islamic Revolutionary Guard Corps, Qasem Soleimani, top leaders agree to keep the government in place.

They also agree to stamp out the protest movement -- by force if necessary.

After a major strike and continuing demonstrations, protesters on November 27 torch the Iranian consulate in the holy city of Najaf.

The following day, 46 protesters are killed and about 1,000 wounded across Iraq.

- PM resigns -

On November 29, Sistani calls for a new government. On December 1 Abdel Mahdi resigns.

On December 6, Sistani urges the nomination of a new prime minister to be carried out without foreign interference.

At least 20 protesters and four police officers are killed in Baghdad when gunmen attack a building where anti-government protesters had been camped out for weeks.

Protests intensify from December 22.

On January 3, 2020, Soleimani and a pro-Iran leader Abu Mahdi al-Muhandis are assassinated in Baghdad in a US strike.

The protest movement pauses amid tensions between Washington and Tehran.

But on January 10, thousands of Iraqis rally across the country, with more protests 10 days later. Security forces break up demonstrations with live fire.

- New government -

On February 1, Mohammad Allawi is chosen to form a new government. But he gives up a month later, having not received a quorum for a vote of confidence in parliament.

On March 17, the former governor of the holy city of Najaf, Adnan Zurfi, is charged with replacing him.

But Zurfi faces rare political consensus against him, and he drops out.

On April 9, spy chief Mustafa al-Kadhemi is asked to form a government.

In May, he is sworn in and vows to "hold to account all those who shed Iraqi blood".

On July 31, Kadhemi sets an early parliamentary vote for June 6, 2021, nearly a year ahead of schedule.