Early Years: Saleh and the Houthis
1990’s – After the reunification of Yemen, Ali Abdullah Saleh transitions from president of North Yemen—a post he had held since 1978—to president of the Republic of Yemen. At the same time, the Zaidi-Shia group Ansar Allah—or the Houthis—gradually gain power; the group’s rise has the tacit support of President Saleh.
1994: Civil War – Just years after the reunification of Yemen, the unintegrated armies of the north and the south face off, resulting in a brief civil war that resulted in the defeat of the southern army and shored up Yemen’s reunification.
2000 – Saleh reaches a border demarcation agreement with Saudi Arabia (Treaty of Jeddah) and seeks to disarm the Houthis, whom he had viewed previously as a useful cudgel against Saudi interference in Yemen.
2004-2010: Houthi Rebellion
Tensions run high between Saleh’s government and the Houthis—led by Hussein Badreddin al-Houthi—after Saleh’s border deal with Saudi Arabia. Al-Houthi eventually leads a rebellion against the Yemeni government in 2004.
June-September 2004 – Starting in June 2004, Saleh’s government begins arresting hundreds of Houthi members and issues a reward for Hussein Badreddin al-Houthi’s arrest. Fighting continues until al-Houthi is killed in September.
March-June 2005 – Fighting between the Houthis—now led by Hussein’s brother, Abdul-Malik al-Houthi—and government forces surges, leaving hundreds dead. Fighting ceases after the sides reach an agreement, resulting in the surrender of the Houthis’ top military commander.
2005-2006 – Sporadic clashes between the government and the Houthis continue, but in March 2006, Saleh grants amnesty to 600 Houthi fighters. Saleh goes on to win the 2006 election.
January-June 2007 – Early in 2007, the Houthi rebels and Saleh’s government again find themselves at odds. Fighting continues for five months until Abdul-Malik al-Houthi reaches a ceasefire agreement with Saleh with the help of Qatar.
April-July 2008 – The ceasefire had not turned a year-old when more fighting breaks out between the government and the rebels. By July, Ali Abdullah Saleh declares an end to the fighting in the Houthi-dominated Saada governorate.
2009-2010: Operation Scorched Earth – In August 2009, the Yemeni military launches Operation Scorched Earth to crush the Houthi rebellion in Saada. At this point, Houthi rebels begin fighting with Saudi forces in cross-border clashes. Fighting continues until, after rounds of offers and counteroffers, Saleh’s government agrees to a ceasefire with Abdul-Malik al-Houthi and the rebels in February 2010. The Yemeni military simultaneously carries out Operation Blow to the Head, a crackdown on both the rebels and al-Qaeda in the Arabian Peninsula (AQAP).
September 2010 – Government forces besiege the governorate of Shabwa in southeast Yemen to root out AQAP militants.
2011: Arab Spring Reaches Yemen
January 2011 – Demonstrations calling for the end of Saleh’s 33-year rule begin. Saleh offers some concessions—promising not to seek reelection—but the protests spread. Security forces and Saleh supporters launch a crackdown that eventually leaves between 200 and 2,000 people dead.
April 2011 – Saleh’s General People’s Congress (GPC) agrees to a Gulf Cooperation Council (GCC)-brokered deal to hand over power, but the president refuses to sign on. This prompts the influential Hashid tribal federation and several army commanders to back the opposition, after which clashes erupt in Sanaa.
June 2011 – Saleh is seriously injured in a bombing and travels to Saudi Arabia for medical treatment.
September 2011 – Saleh returns to the presidential palace amid renewed clashes. It is not until November 2011 that he signs a deal that has his deputy, Abdrabbuh Mansour Hadi, assume power and form a unity government.
February 2012 – Hadi is sworn in for a two-year term as president after an election in which he stood unopposed.
Post-Arab Spring: Unity Government and Houthi Takeover
January 2014 – The National Dialogue Conference concludes after ten months of deliberations, agreeing to a document on which the new constitution would be based.
February 2014 – A presidential panel approves a political transition plan for Yemen that organizes the country into a federation of six regions.
August 2014 – Following two weeks of anti-government protests, President Hadi dissolves his cabinet and overturns a controversial rise in fuel prices.
September-October 2014 – The Houthis take control over most of Yemen’s capital, Sanaa. The following month the rebels seize the Red Sea port city of Hodeida.
January 2015 – After being placed under house arrest by the Houthis, Hadi resigns as president. Despite previous attempts to craft a power-sharing agreement between Hadi and the Houthis, the two had continued to clash. The Houthis later reject a draft constitution proposed by Hadi’s government.
February 2015 – The Houthis take control of the Yemeni government, a move swiftly denounced by the United Nations. President Hadi flees the presidential palace in Sanaa and escapes to Aden, where he later rescinds his resignation, declaring himself the legitimate president, and deems the Houthi takeover a “coup.”
March 2015 – The Islamic State claims its first major attacks in Yemen, setting off two suicide bombs at Shia mosques in Sanaa. The Houthis start an offensive against government forces, advancing toward southern Yemen. President Hadi flees Aden and takes refuge in Saudi Arabia. Shortly thereafter, the Houthis seize parts of Taiz.
Saudi-led Coalition and Civil War
March 2015: Operation Decisive Storm – After repeated pleas from Hadi, a Saudi-led coalition of Arab states—including the United Arab Emirates, Egypt, Morocco, Jordan, Bahrain, Sudan, and Kuwait—initiates Operation Decisive Storm in support of the ousted president. The coalition launches air strikes against Houthi targets, deploys small ground forces, and imposes a naval blockade. The United States announces its intention to aid the coalition’s efforts.
April 2015: Operation Restoring Hope – The coalition declares an end to Operation Decisive Storm. Saudi Arabia announces it would move on to a phase described as Operation Restoring Hope. Despite the announcement, the Saudi-led coalition continues to bomb Houthi positions and the United States increases its arms sales for the Saudi campaign in Yemen.
April 2015 – Despite the bombing campaign, the Houthis capture the city of Ataq. After three Saudi officers die in a Houthi attack at the Saudi border, Saudi Arabia boosts its border security. The Houthi fighters also condemn a UN Security Council resolution imposing an arms embargo on the group, calling the decision an act of “aggression.”
May 2015 – Ali Abdullah Saleh had previously been accused of siding with the Houthi rebels in support of Hadi’s ouster; in May, Saleh and Yemeni forces loyal to him announce a formal alliance with the Houthis. The Saudis and Houthis agree to a five-day “humanitarian ceasefire.” US President Barack Obama convenes a GCC meeting at Camp David to resolve the crisis in Yemen, but only two states send their leaders.
August 2015 – After months of fighting with Sunni tribesmen and AQAP militants, the Houthis take control of the entire Shabwah governorate.
September 2015 – President Hadi returns to Aden after Saudi-backed government forces and those loyal to Hadi recapture the port city from Houthi forces.
April 2016 – The United Nations sponsors talks between the Hadi government and the coalition of Houthis and former President Saleh’s General People’s Congress.
October 2016-May 2017 – Both sides of the conflict allegedly break ceasefires. The United Nations and others try to broker peace talks and political resolutions. The Houthis claim responsibility for firing missiles into Saudi Arabia, including at the capital, Riyadh.
May-November 2017 – Humanitarian agencies and watchdogs decry the Yemen crisis as one of the worst humanitarian emergencies in the world. There are thousands of civilians dead and wounded, an outbreak of cholera, and a potential famine that would leave thousands on the brink of starvation.
November 2017 – Saudi Arabia intercepts a missile fired toward its airport in Riyadh and blames the Houthis, Iran, and Lebanon’s Hezbollah for escalating the war.
December 2017 – After Saleh had reversed course and sided with the Saudi-led coalition, fierce fighting in Sanaa between the Houthis and forces loyal to Saleh leaves the former president dead. The Houthis control much of northern Yemen but face stiff opposition from the Saudi-led coalition. President Hadi—whose loyalists control much of south Yemen—has called for a popular uprising against Houthi rule in the north. Saleh’s son, Ahmed Ali Saleh, has vowed revenge against the Houthis for his father’s assassination.
January 2018 – In a firefight, the Southern Transitional Council (STC), the United Arab Emirates-backed separatist movement seeking a revival of the formerly independent South Yemen, seizes control of Aden, Yemen’s main southern city and government headquarters. By March, 22 million Yemenis require humanitarian aid.
February 2018 – The United Nations appoints longtime British diplomat Martin Griffiths as Special Envoy of the Secretary-General for Yemen.
March-May 2018 – Fighting escalates along Yemen’s western coast and dozens are killed in Saudi air strikes and security raids. A Saudi-led coalition drone strike kills Saleh Ali al-Sammad, president of Yemen’s Supreme Political Council, making him the most senior Houthi casualty since the coalition began its activities in 2015. International opposition to the coalition’s operations grows after an air raid kills more than 20 at a wedding party. In May, UAE forces take over the island of Socotra, occupying the airport and seaport and causing tensions with Yemeni government officials.
June-July 2018 – Yemeni President Abdrabbuh Mansour Hadi meets with UAE Crown Prince Mohammed bin Zayed Al Nayhan and, by July, the coalition launches an offensive on the port city of Hodeida.
August-October 2018 – International furor over the Saudi-led coalition’s war in Yemen grows after an air raid strikes a school bus, killing 40, mostly children. Public opinion of US support for the war effort in the United States plummets as it is reported that the bomb used in the air raid was US-supplied. In October, US resident and Washington Post columnist Jamal Khashoggi is assassinated by Saudi agents in Istanbul, raising additional questions about US support for Riyadh’s war on Yemen. UN efforts to mediate between the Yemeni government and the Houthi rebels in Geneva, Switzerland are fruitless.
November-December 2018 – The US political establishment begins to agitate for withdrawing US support from the Saudi-led coalition in Yemen. Former Obama Administration officials—including future Secretary of State Antony Blinken, future UN Ambassador nominee Linda Thomas-Greenfield, and future National Security Advisor to President Joe Biden Jake Sullivan—sign an open letter expressing remorse for their support for the war and urging all sides to end the fighting. In December 2018, the US Senate, for the first time, votes to invoke the War Powers Resolution to force the US military to end its participation in the Yemen war.
Later that month, after UN-mediated talks, the Yemeni government and the Houthis sign the Stockholm Agreement that includes prisoner swaps, a mutual redeployment of forces away from Hodeida Port, and a committee to discuss the contested city of Taiz. The cease-fire is set to take effect on December 18. Overall, the Stockholm Agreement fails to achieve its goals and neither side agrees to withdraw from Hodeida.
January-June 2019 – Fighting continues. Houthis launch a drone attack on Al-Anad Air Base north of Aden, injuring dozens and killing the head of Yemeni intelligence. By June, the UAE unilaterally scales back its military presence in Yemen while continuing to support the STC, which had seized more power in Aden. Meanwhile, the Houthis step up efforts to attack Saudi territory, including launching missiles at oil installations and airports. Saudi and Yemeni forces capture Abu Osama al-Muhajer, leader of the so-called Islamic State-Yemen Province (IS-YP).
In Washington, Secretary of Defense James Mattis’s resignation in December 2018 takes effect in February 2019, marking an end to the Trump Administration’s efforts to engage in the Yemen peace process. In April, President Donald Trump vetoes a bipartisan congressional measure that would force the US military to end its role in the Yemen war.
July-September 2019 – The UAE announces it has completed its troop drawdown in Yemen, but by August, the STC effectively assumes control of the southern governorates of Aden, Abyan, and Shabwa. By the end of August, UAE forces conduct air raids against Yemen government forces headed to Aden to regain control.
In August, the Houthis launch “Operation Victory from God” against Saudi-led forces and the group continues to escalate its attacks on Saudi oil installations. In September, the Houthis claim to have used drones to bomb oil processing facilities in Abqaiq and Khurais in eastern Saudi Arabia. The attacks result in Saudi Arabia losing about half of its output capacity and, while the Houthis take credit for the aggression, the international community blames Iran because it was thought to have provided the technical expertise needed to carry out such attacks.
November 2019 – In an effort to end the fighting between ostensible coalition partners in southern Yemen, Saudi Arabia and the UAE broker a power-sharing agreement between their respective partners in the Yemen government forces and the STC. The Riyadh Agreement is signed in early November, but by December, clashes between the two resume.
January-February 2020 – Fighting between the Saudi-led coalition and the Houthis picks up. Houthi forces carry out missile attacks on military training camps and in Saudi Arabia’s southern provinces. They claim to “liberate” roughly 1,550 square miles of territory in the al-Jawf and Marib governorates from Saudi-led forces, a claim the coalition denies.
March 2020 – Houthi forces capture the strategic city of al-Hazm in the al-Jawf offensive and Saudi forces carry out a retaliatory air strike on Sanaa. This occurs as the United Nations urges maintaining the cease-fire during the COVID-19 pandemic to prevent its spread in Yemen.
The Trump Administration announces a freeze on $73 million in humanitarian aid to Yemen, fearing the Houthi rebels would control the assistance.
April-May 2020 – In April, Saudi Arabia initiates a unilateral two-week cease-fire to mitigate the risks of the new coronavirus pandemic. Days later, Yemen records its first known case of COVID-19. Despite the cease-fire, the Houthis and the Saudi-led coalition are accused of carrying out attacks. In the south, the STC once again demands self-rule, breaking its agreement with the national government.
June-November 2020 – In June, the Southern Transitional Council deposes the recognized government in Socotra, with government supporters decrying the move as a coup d’état. The following month, the STC says it has renounced its claim to self-rule and will return to the previously agreed-upon power-sharing structure.
In October, the warring sides in Yemen carry out the conflict’s largest prisoner swap. By November, Saudi Arabia and the Houthis have reportedly initiated back channel talks, with Saudi officials indicating their willingness to sign a cease-fire deal and end the Saudi air and sea blockade in exchange for the creation of a buffer zone between Houthi-controlled territory in Yemen and the kingdom’s borders. The Houthis later claim to have fired a missile at the coastal Saudi city of Jeddah.
December 2020 – The STC and the Hadi government formalize a new power-sharing agreement in Aden. Prime Minister Maeen Abdulmalik Saeed is reappointed as head of the Hadi government’s new cabinet, with seats going also to both the STC and Yemen’s Islah Party. Just weeks later, as the new cabinet arrives in Aden from Saudi Arabia, an attack on the airport kills at least two dozen people, but no ministers. The Hadi government, the STC, and much of the international community blame the Houthis for the attack and Saudi warplanes conduct retaliatory raids on Sanaa.
January 2021 – The Trump Administration uses the December attack to justify designating the Houthis as a foreign terrorist organization (FTO). The Houthis are still able to consolidate control over 70-80 percent of the Yemeni population and threaten Marib, a stronghold near the northeast corner of their control zone.
President Biden Takes a New Path
February 2021 – President Joe Biden announces changes to US policy toward Yemen, including revoking the Houthi FTO designation, declaring an end to US support for the Saudi-led coalition’s offensive operations in the conflict, appointing Timothy Lenderking as a special envoy for Yemen, supporting the UN-led peace process, and providing assurances to Saudi Arabia regarding the defense of its territory.
Houthi rebels launch an offensive in Marib city, the final stronghold of government forces in the north and near some of northern Yemen’s richest old fields. Marib hosts nearly one million Internally Displaced Persons (IDPs), and intense clashes are expected to displace thousands more.
March 2021 – Conflict between the Hadi government and the Houthis escalates in Marib governorate. The fighting coincides with ongoing Houthi missile and drone attacks against Saudi oil facilities, airports, and airbases. Saudi Arabia retaliates with airstrikes, particularly in Sanaa. The US condemns Houthi actions. Riyadh proposes a ceasefire, which includes reopening of Hodeida seaport and Sanaa airport. Houthis reject the proposal on the grounds that a full lifting of the ongoing blockade is a prerequisite for any such agreement.
April-May 2021 – Strikes and counterstrikes continue and escalate. The UN Security Council and Iran’s Foreign Minister Mohammed Javad Zarif voice their support for a ceasefire between the various Yemeni actors. In a discussion with Saudi Crown Prince Mohammed bin Salman, the US’s Lenderking pushes for the Saudi-led coalition to loosen the blockade on Hodeida and Sanaa. The Houthis refuse to meet with then-UN Special Envoy for Yemen Martin Griffiths to discuss de-escalation of the conflict.
August 2021 – Amid continued air attacks from Houthi rebels, the Biden Administration removes its most advanced missile defense systems from Saudi Arabia. The withdrawal follows a Houthi attack that wounded eight civilians on Saudi soil and damaged a commercial airliner.
The UN outgoing special envoy for Yemen announces nearly 20 million people, or two-thirds of the country’s population, are dependent on humanitarian aid for daily needs. Five million “are one step away from succumbing to famine and the diseases that go with it,” he warns.
As Houthis continue to gain ground against Hadi government forces in Marib, Oman attempts to broker a peace deal between Saudi Arabia and the Houthis. Houthi negotiators refuse to meet with the newly appointed UN Special Envoy for Yemen, Hans Grundberg, before the Saudi-led coalition commits to the full lifting of the blockade on Hodeida and Sanaa.
September 2021 – After a lull in hostilities, Houthi rebels renew their offensive in the Marib Governorate. The rebels capture Rahabeh, a key district in the south of Marib. Government forces had recaptured Rahabeh from Houthi control in July 2021. The Houthis continue to make progress in the battle for Marib city.
Government security forces forcefully respond to widespread protests across southern Yemen, killing three protesters. Yemeni people take to the streets over the collapse of Yemen’s currency and inaccessibility of basic daily necessities.
On September 18, Houthis execute nine people on charges of involvement in the Saudi-led coalition airstrike in April 2018. The strike killed Saleh Ali al-Sammad, the Houthi-aligned de facto president of Yemen.
On September 27, a US official delegation (including National Security Advisor Jake Sullivan, Timothy Lenderking, and the NSC’s Coordinator for the Middle East and North Africa Brett McGurk) meet with Mohammed bin Salman and Deputy Defense Minister Khalid bin Salman to push for a diplomatic solution for the conflict.
October 2021 – The United Nations Human Rights Council votes against renewing the mandate for the Group of Eminent International and Regional Experts on Yemen (GEE), the only independent body monitoring all parties to the conflict. Saudi Arabia is accused of attempting to shut down the investigation, which in 2018 reported possible war crimes committed by all parties.
Clashes continue around Marib between Hadi government and the Houthis. On October 17, Houthis gain control of the Usaylan, Bayhan, and Ain districts of Shabwa Governate and the al-Abdiyah and Harib districts of Marib Governate.
November 2021 – Houthis seize the former premises of the US Embassy in Sanaa, detaining local employees. The United States calls for their immediate release and demands that the Houthis vacate the premises.
Houthi spokesperson announces capture of Marib’s al-Jubah and Jabal Murad districts, after last month taking al-Abdiyah and Harib. Government forces prepare to defend their last remaining northern stronghold, Marib city. Some two-million civilians are now trapped in Marib Governorate.
Coalition-aligned forces abandon their position in the port city Hodeida, allowing rebels to retake the city. A 2018 cease-fire agreement prohibited fighting between the two sides, and government forces state they are withdrawing troops from Hodeida to send them to reinforce the front lines.
December 2021 – Due to falling international funding, the World Food Program (WFP) cuts food aid to Yemen. In November 2021, WFP targeted 11.1 million for food assistance. The cost of food dramatically increases as the humanitarian situation deteriorates.
January – February 2022 – Houthi rebels launch a series of unprecedented attacks against the United Arab Emirates and Saudi Arabia, including air attacks across the border and seizing a UAE vessel in the Red Sea. The Saudi-led coalition responds with a bombing campaign in Sanaa, an attack on a northern prison, and a strike on a telecoms facility in Hodeida resulting in a four-day internet blackout across the country. UAE-backed forces regain control of areas near Marib.
On February 23, the US Treasury Department announces new sanctions against individuals involved in a funding network for the Houthis.
The United Nations Security Council renews for one year its arms embargo on Yemen, and continues a travel ban and asset freeze on actors who threaten the peace. The Council condemns Houthi attacks on Saudi Arabia and the UAE that struck civilians and civilian infrastructure. (Four countries abstain: Mexico, Ireland, Norway, and Russia).
March 2022 – On March 6, the Houthis reach an agreement with the United Nations to address the issue of an abandoned oil tanker in the Red Sea, the FSO Safer, that posed a threat of a massive oil spill.
The World Food Program declares that the humanitarian situation in Yemen is worsening because of the Russian war on Ukraine.
Houthis continue attacks against Saudi oil facilities, while the coalition continues its strikes against Sanaa and Hodeida.
GCC-sponsored talks in Riyadh begin between the various parties to the Yemen conflict. The Houthis decline to participate, stating that they should be held in a neutral country. Saudi Arabia announces on the same day the cessation of all military operations in Yemen as of March 30.
April 2022 – The UN brokered a two-month truce between warring parties that is to begin with the holy month of Ramadan. The agreement is a notable step toward peace, as the last nationwide coordinated cessation of hostilities was during peace talks in 2016.
As peace efforts gain traction with a two-month ceasefire, exiled President Abdrabbu Mansour Hadi transfers powers to a new Presidential Leadership Council. Led by Rashad al-Alimi, members of the council were selected at GCC-sponsored talks in Riyadh, and include individuals associated with the secessionist Southern Transitional Council as well as those formerly part of the government under Hadi. Hadi fires Vice President Ali Mohsen al-Ahmar, who has long been resented by the Houthis, and delegates his powers to the presidential council. After the transfer of power is announced, Saudi Arabia and the UAE say they will provide $3 billion to support Yemen’s decimated economy.
Despite the two-month truce, Houthi forces resume attacks on the front lines of the battle for Marib which have been static since February, when UAE backed forces pushed Houthis out of the center of the Hareb district.
Houthi rebels sign an “action plan” to prevent the recruitment and use of children in armed conflict. A senior Houthi military official had said in 2018 that the group inducted 18,000 child soldiers into its army, some of whom as young as 10 years old.
This timeline was created with the assistance of ACW’s past and current interns Gabriella Haedelt, Numan Aksoy, Brandan Hadeed, and Hannah Jacobs.
Photo credit: flickr/Rod Waddington