12 September 2012 Last updated at 05:43 ET

Yemen profile

• Overview
• Facts
• Leaders
• Media
• Timeline

Yemen has been at the crossroads of Africa, the Middle East and Asia for thousands of years thanks to its position on the ancient spice routes. It is one of the possible locations for the Biblical kingdom of Sheba.

The Romans knew this fertile country as Arabia Felix, in contrast to the relatively barren Arabia Deserta to the north.

The modern Republic of Yemen was born in 1990 when traditional North Yemen and Communist South Yemen merged after years of clashes. Since unification Yemen has been slowly modernising and opening up to the world, but still retains much of its tribal character.

A short civil war in 1994 ended in defeat for separatist southerners, but regional tensions re-emerged in the summer of 2009 when government troops and Houthi rebels from the Shia Zaidi sect clashed in the north, killing hundreds and displacing more than a quarter of a million people.

At a glance

• Politics: President Saleh finally ceded power in November 2011, after months of protests. His departure paved the way for political reform process
• Economy: Yemen is the poorest country in the Middle East; economic difficulties have sparked unrest
• International: Yemen's al-Qaeda insurgency is causing concern in the region

Country profiles compiled by BBC Monitoring

Yemen was hit by more serious political upheaval early in 2011 when protesters - inspired by the Arab Spring uprisings in Tunisia and Egypt - rallied against the three-decades-old rule of President Saleh. He stepped down as part of a deal brokered by neighbouring countries at the end of the year, ushering in a transitional period of political reforms.

Al-Qaeda

In the meantime, Yemen had become a major base for Islamic militants after the crackdown on al-Qaeda closed their traning bases in Afghanistan and Pakistan. The Yemeni branch of al-Qaeda was behind a failed attack on a US airliner on Christmas Day 2009, prompting greater government efforts to crush the insurgents.

Truce with the Houthi rebels in February 2010 allowed the government to focus on al-Qaeda and resurgent southern separatists, but the anti-government uprising in 2011 gave al-Qaeda a chance to establish several strongholds in Abyan province.

Since then government forces and al-Qaeda have battled for control of several towns in the south, while the US has used unmanned drones against the Islamists.

The ancient town of Shibam with its mud brick tower houses has been described as the Manhattan of the desert