Yemen is back in the global spotlight after the Iran-aligned Houthi group earlier this month made military gains against the forces loyal to the internationally recognised government, tightening its grip over the Red Sea coast.

The latest escalation in the Arab region’s most impoverished nation follows a period of relative calm that had largely held since the United Nations-brokered ceasefire in 2022 between the Iran-aligned group and the Saudi-backed Yemeni government.

The Houthi takeover of northwestern Yemen, including the capital Sanaa, in 2014 had drawn Saudi military intervention. The fighting left tens of thousands dead and millions displaced, creating a humanitarian crisis.

In 2023, Saudi Arabia and the Houthis agreed to a UN roadmap towards a permanent ceasefire after direct talks, but the roadmap was never formalised.

Here’s a simple guide to Yemen’s war, from the Houthi takeover in 2014 to the latest escalation.

From the 2014 Houthi takeover to the expansion of the Saudi-backed government

• The Houthis took over vast swaths of northwestern Yemen, including the capital, Sanaa, in September 2014, and months later assumed control of the government, forcing President Abd-Rabbu Mansour Hadi to flee to Aden and then to Saudi Arabia.
• Alarmed by the rise of the Iran-aligned Houthis on its border, Saudi Arabia intervened in support of the internationally recognised government of Hadi in March 2015, carrying out thousands of attacks. Saudi Arabia sees Iran as a regional threat due to the latter’s financial and military power, as well as support for armed groups like Hezbollah.
• In this period, Houthi rebels targeted strategic infrastructure across Saudi Arabia and the United Arab Emirates (UAE), including airports, gas fields and oil tankers in the Red Sea. According to data analysis by the Center for Strategic and International Studies, Saudi Arabia’s military intercepted more than 4,000 Houthi missiles, drones and other standoff weapons between 2017 and 2022.
• In 2019, the UN reported that about 24 million people (80 percent of the population) needed some form of assistance, making Yemen “the world’s worst humanitarian crisis” after nearly five years of war. The country also experienced the world’s worst cholera outbreak, amid the war‑damaged health and water systems. Millions of people were exposed, and hundreds of thousands of suspected cases were recorded.
• After seven years of conflict, the UN-mediated truce took effect in April 2022, bringing a marked de-escalation in fighting, even while a low-intensity conflict had remained since.
• In January of this year, Yemen’s internationally recognised government expanded its control of the southern and eastern parts of the country from the Southern Transitional Council (STC), a UAE-backed separatist group. The STC delegation announced its dissolution after government forces took back control.
• The UAE’s backing of the STC, which called for the secession and independence of southern Yemen, strained Saudi-UAE ties, with Riyadh asking the Emirati forces to leave the country.

Who are the main players?

The Houthis

The Houthis, also known as Ansar Allah (supporters of God), are an armed group in control of mainly northwestern Yemen and several areas close to Saudi Arabia. Since September 10, they have tightened control over the country’s Red Sea coast, a vital shipping lane.

The Houthis from Yemen’s Zaidi Shia minority emerged in the northern mountainous region of Saada in the 1990s, demanding a greater share of power.

They capitalised on the widespread public anger against the weak transitional government that came to power after longtime President Ali Abdullah Saleh was forced to step down following the 2011 Arab Spring protests.

The Houthis initially allied with military units loyal to former President Saleh as they captured the Red Sea port of Hodeidah in October 2014. In January 2015, they seized the presidential palace in Sanaa, forcing President Abd-Rabbu Mansour Hadi to flee to the southern port city of Aden. Hadi later moved to Saudi Arabia, from where he ran his government-in-exile until his resignation in 2022.

The Houthi group then spent years, with Iran’s backing, fighting a military coalition led by Saudi Arabia.

Seen as part of a regional alliance known as the “axis of resistance” and backed by Iran, the Houthi group nevertheless has its own base, its own interests, and its own ambitions.

The group has gained international prominence for its attacks on Israel and shipping in the Red Sea since the start of Israel’s genocide in Gaza in October 2023.

Saudi Arabia

Riyadh entered the Yemen war when it led a military coalition against the Houthis in March 2015, seeking to restore the government of then-President Hadi.

Houthis have accused Riyadh of carrying out hundreds of attacks in support of the internationally recognised government battling the Houthis in the latest fighting.

Presidential Leadership Council

The PLC was established in 2022 when former President Hadi formally transferred his powers to the new eight-member body.

It represents the internationally recognised government of Yemen, with a mandate to manage the country’s political, security and military affairs, and to steer negotiations towards a permanent ceasefire. It is chaired by Rashad al-Alimi, an adviser to Hadi and former interior minister with the government of the late President Saleh.

Its membership is drawn from a mix of northern and southern politicians and military-linked leaders in a bid to unite major anti-Houthi forces under one roof.

The PLC is backed by Saudi Arabia and the alliance that Riyadh leads. Since taking over complete control of southern Yemen after the dissolution of the STC, the PLC aims to unite Yemen, including the areas controlled by the Houthis.

Islah party

The Yemeni Congregation for Reform, better known as Islah, is a Sunni Islamist movement with historical ties to the Muslim Brotherhood. It is a faction within the recognised PLC-led government but has long had an independent identity. Its major stronghold has long been Marib, the country’s sole gas-producing region with one of its largest oilfields.

National Resistance Forces

The National Resistance Forces is a government-aligned military faction led by Tareq Saleh, nephew of the late former President Saleh.

The force has maintained ties to Saudi Arabia and, like the Islah party, is part of the PLC. It aims for a unified Yemen, positioning itself as a counterweight to both the Houthis and southern secessionists.

Who controls what in Yemen?

The Houthi movement controls Sanaa, the capital, and most of northwestern and northern Yemen, including the entire Red Sea coastline and the Bab al-Mandeb strait, one of the busiest global maritime routes. The control over Bab al-Mandeb by the Iran-aligned Houthis has raised concerns about navigation amid the closure of the Strait of Hormuz by Iran in response to the US-Israel war on Tehran.

The internationally recognised government, meanwhile, controls much of the rest of the country.

What is the humanitarian situation?

More than 112,000 people have been displaced in Yemen and close to 3,000 have fled the conflict to Djibouti, according to the UN.

The International Organization for Migration estimated that 22 million Yemenis, nearly half the population, are in urgent need of humanitarian aid.

The UN Security Council, meanwhile, has condemned the Houthis’ continuing attacks on Saudi Arabia, saying they have caused civilian casualties, including women and children, and damaged energy infrastructure.

What do we know about the latest fighting?

Tensions escalated in July after Yemen’s government forces claimed an attack on an airport in Sanaa, preventing an aircraft from Iran from landing. More attacks followed, and it further escalated in late August when the Houthis launched a major offensive, saying the 2022 truce had been violated by government forces.

The Saudi Arabia-led coalition on Saturday evening said on X that it “successfully intercepted and destroyed” a missile attack attempting to target Riyadh – the first attack on the capital since the Yemen conflict erupted in July.

The coalition added that the Houthis had tried to target “civilians and civilian infrastructure” in several cities in the west of the kingdom, including the port of Yanbu on the Red Sea, an important export hub for Saudi oil, which were additionally thwarted.

The Houthis confirmed they had targeted “sensitive sites” in Riyadh, as well as Aramco facilities in Yanbu.

“The message from the Yemeni group is that despite the Saudi bombardment campaign across Yemen, it will continue to step up its attacks and meet escalation with escalation,” said Al Jazeera’s Yousef Mawry, reporting from Sanaa.

The incident comes days after Riyadh accused the Houthis of targeting Mecca on Wednesday, denouncing it as a “cowardly terrorist attack” on Islam’s holy city. The Houthis strongly denied the accusation, calling it a “worn-out lie”.

Meanwhile, on the ground in Yemen, the armed forces of the Saudi-backed internationally recognised government and the Houthis are engaged in fierce fighting in southern Marib as well as Taiz, Lahj, al-Jawf and al-Bayda.

The Yemeni army also said 13 soldiers were killed in two days of clashes with Houthi forces in the southwestern provinces of Taiz and Lahj.

On September 10, the Houthis made their most crucial gain in this bout of fighting by seizing the crucial Red Sea city of Mocha, expanding control over the strategic Bab al-Mandeb strait.

Despite appeals from Riyadh for United States President Donald Trump to strike the Houthis directly, Washington has so far held back, wary of opening a new front while still fighting a costly war with Iran.

Meanwhile, US officials have met Houthi representatives in Oman over the weekend. The Houthis reportedly assured Washington that vessels not linked to Saudi Arabia would not be targeted.

The Houthis have banned the passage of Saudi ships, adding pressure on Riyadh, which has used the Red Sea as an alternative to the Strait of Hormuz. Last week, the Houthis also attacked the East-West pipeline, disrupting the export of Saudi oil and causing global oil prices to cross $100 per barrel.