In 2014, Houthi rebels from the far north of Yemen, backed by supporters of ousted president Ali Abdullah Saleh, over-ran the capital, Sanaa. Saleh's sucessor, President Abd Rabbuh Mansur Hadi, fled to the southern city of Aden and later to Saudi Arabia as the Houthi/Saleh alliance rapidly extended its control to other parts of the country.
This prompted intervention by a Saudi-led military alliance which began in 2015 and was still continuing more than a year later. The intervention took the form of an intensive and highly destructive aerial bombing campaign, coupled with the use of unknown numbers of ground forces, including mercenaries, from a variety of countries
Who are the Houthis?
The Houthis – so called after the most prominent family in their movement – are officially known as Ansar Allah ("The Supporters of God"). They belong to the Zaidi sect, a branch of Shia Islam found mostly in Yemen which is thought to account for 35%-40% of the country's population.
Their first leader, Hussain Badreddin al-Houthi, the son of a prominent Zaidi scholar, was initially involved in al-Haqq ("The Truth"), a small political party which was allowed to win two seats in the 1993 parliamentary election. Houthi himself served as a member of parliament between 1993 and 1997.
The Houthis also began to attract attention through a movement called al-Shabab al-Mu'min ("Believing Youth") whose teenage members caused disruption at mosques in various parts of the country by chanting "Death to America, Death to Israel" after Friday prayers. The youths were often often arrested – only to return later and do it again.
Believing Youth had begun as a local effort to defend Zaidi rights in the Saadah region, gradually expanding to provide educational and social services but later becoming increasingly political in its opposition to the Saleh regime's perceived pro-American stance.
The Houthis' grievances
Although Yemen had once been ruled by Zaidi imams and President Saleh was also a Zaidi, the Zaidis of the Saada area had become a marginalised group. Left largely to their own devices, they had become extremely self-reliant, organising their own affairs and constructing much of the rudimentary local infrastructure themselves in the absence of government help.
In addition to that, they felt their religious traditions were threatened by Saudi influence as increasing numbers of men converted from Zaidism to the salafi or Wahhabi version of Sunni Islam. Converts included men who occupied the bottom of the traditional hierarchy and bitterly resented their social disadvantage, as well as youths who resented the power of the older generation or were attracted by the charisma of salafi leaders and their obvious financial resources. Speaking at a conference in 2013, Yemen expert Shelagh Weir explained:
"Certain sheikhs openly or tacitly supported salafism for personal or anti-Zaidi reasons or because of the subsidies they received from Saudi Arabia ...
"During the 1990s the growth of socially-divisive salafism within the heartlands of Zaidi Islam was encouraged and funded by officials and business interests in Saudi Arabia and in Yemen – including President Ali Abdullah Saleh.
"Salafis increasingly mocked or questioned the beliefs and rituals of the Zaidi majority, threatening them in mosques and accusing them of wanting the return of the imam [i.e. the end of the republican system] – though this was publicly denied by the Zaidi clerics."
Bernard Haykel described the Zaidis' religious concerns and their initial response to them in an article for the American Institute for Yemeni Studies in 1995.
In 2004, armed conflict broke out in Saada, resulting (according to government officials) in the deaths of at least 98 Houthi supporters and 32 members of the security forces.
The authorities denounced Hussain al-Houthi for "harming Yemen's stability and interests" and offered a reward of $55,000 for his capture. They accused him of highway robbery, setting up unauthorised religious schools, raising the Hizbullah flag, damaging a water project, urging citizens to withhold taxes, attacking mosques and declaring himself Imam – a title not used in Yemen since the 1962 republican revolution.
Shortly afterwards, Hussain al-Houthi was killed, apparently by security forces during an attempt at a mediated peace settlement. Predictably, this exacerbated the Zaidis' grievances.
Between 2004 and 2010 the Houthis and the Saleh regime fought a series of six intermittent wars. The most serious of these began in August 2009 when the government launched "Operation Scorched Earth" against the rebels. That phase of the conflict ended in February 2010 when both sides agreed a ceasefire.
'Operation Scorched Earth'
There was little first-hand reporting of the 2009-2010 war because of media exclusion from the area. The scale of casualties is unknown but many thousands of people fled their homes, resulting in a serious humanitarian crisis. The following blog posts trace the course of the conflict:
Saudi Arabia became militarily involved in the 2009-2010 war, launching airstrikes in support of the Saleh regime. The Saudis also became concerned about security on their porous border with Yemen and the ethnically Yemeni population in the south-west of the kingdom. (The Houthis, close to Saudi Arabia on the other side of the border, appeared not to recognise the 1934 Treaty of Ta'if which had formally ceded to territories of Asir, Najran, and Jizan to Saudi Arabia.)
The Saudis therefore declared a security/exclusion zone on their own side of the border, forcibly uprooting tens of thousands of people who lived in the area:
Saudi Arabia joins the war
Saudis continue battle with Yemeni rebels
Saudis deport 3,000 to Yemen
Video of 'captured Saudi'
Saudis admit attacks in Yemen
Rebels' challenge to Saudi state
Clearing out civilians
Saudis fanning the flames
Saudi Arabia's border clear-out
Rebels kill three Saudi soldiers
Saudi troops 'enter Yemen'
Yemen 'dragged Saudis into war'
Saudis destroy border communities
A fight to the finish?
Saudis 'torture Houthi rebels'
Saudi bulldozers destroy Yemeni village
Saudis 'used British planes to bomb Yemen'
France 'aided Saudi war on Houthis'
The road to civil war
The fall of President Saleh in 2012 and the ensuing political turmoil created new opportunities for the Houthis – especially when supporters of Saleh, their former enemy, began assisting them militarily.
From small beginnings they had emerged as a real political force – though one among many. Had they been wiser they would probably have settled for that, but by then a thirst for power seemed to be driving them. Seizing control of the capital in 2014, they began imposing their rule on parts of the country where they had little or no public support. The oppressed became oppressors as Yemen descended into civil war.
The Houthis and Iran
The fighting that broke out in Yemen in 2014 has often been characterised as a proxy war between Saudi Arabia and Iran. The words "Houthi" and "Iranian-backed" soon became coupled together in virtually every media report about the conflict. The Houthis have some religious affinity with Iran and nobody – least of all, the Iranians – would deny that Iran has given them encouragement. The question of how much material support they have received from Iran is more difficult to answer, however. The available evidence suggests it has been rather limited and that direct Iranian involvement in Yemen has been far less than that of Saudi Arabia which has a long history of meddling in Yemen's affairs.
Yemen and Iran
Blog post by Brian Whitaker looking at the evidence of Iranian involvement in Yemen. 30 March 2015
Six reasons why Iran won’t join the war in Yemen
By Hassan Ahmadian, Al-Monitor, 7 March 2016
The Conflict in Yemen: A Case Study of Iran’s Limited Power
By Shlomo Brom and Yoel Guzansky, INSS Insight No. 747, 16 September 2015
Iran's Game in Yemen
Why Tehran Isn't to Blame for the Civil War
By Mohsen Milani, Foreign Affairs, 19 April 2015
Iran and the Yemeni rebels
Blog post by Brian Whitaker, 20 October 2009
Constitutional Declaration by the Houthis
6 February 2015
Here come the Houthis
Blog post by Brian Whitaker, 26 September 2014
Yemen and the Houthi conflict
Conference report,15 January 2013
Statement by the Houthis
5 October 2012
Testimony to the Senate Foreign Relations Committee
By Gregory D. Johnsen, 20 January 2010
Weak Foundations: State Failure and the Crisis in Yemen
Elham Manea, 4 May 2010
Yemen: Defusing the Saada Time Bomb
International Crisis Group, May 2009
Yemen: Fear of Failure
by Ginny Hill. Chatham House Briefing Paper, November 2008