A look at Iraq's Anbar province, where President Bush visited Monday for a firsthand assessment of the war:

The Land 

Anbar is the largest of Iraq's 18 provinces, covering nearly 55,000 square miles from the western outskirts of Baghdad to the borders of Syria, Jordan and Saudi Arabia. Most of the territory is desert except for a strip of fertile land along the Euphrates River.

The People

With a prewar population of about 1.2 million, Anbar has the lowest population density of any Iraqi province. The overwhelming majority of the population is Sunni Arab, and tribal loyalties are strong. Many of the Shiites and Kurds who lived before the war in cities such as Ramadi, the capital, Fallujah and Haditha fled after attacks by Sunni religious extremists. Bedouin tribes live in the desert areas, following their flocks of sheep and goats.

The War

Anbar province was the stronghold of the Sunni Arab insurgency, which mobilized in the months following the 2003 collapse of Saddam Hussein's Sunni-dominated regime. Saddam had forged links with the Anbar tribes and rewarded them for their loyalty, buildings factories and other government projects in Ramadi, Fallujah and Haditha.

Many of Saddam's intelligence and Republican Guard officers came from Fallujah. With their patron gone, many Anbaris took up arms and turned to al-Qaida in Iraq to resist the Americans.

Some of the bloodiest fighting of the war took place in Fallujah in 2004 and Ramadi in 2005 and 2006.

All that began to change last year when leaders of the Dulaim tribe broke with al-Qaida in Iraq, angry over the movement's attempt to monopolize power and mandate a strict Islamic lifestyle. Since then, more tribes have turned against al-Qaida and are working with U.S. forces.